Each month, The Dynasty Guru will provide a prospect update that includes notable performances (good and bad), assignments, promotions, trades, injuries, and suspensions. Most importantly, the monthly update will examine prospects with increasing and decreasing fantasy value, from the elite to the obscure.

At the beginning of May, TDG reviewed April performances for infielders, outfielders, and pitchers. In addition, TDG updated the Top 200 Fantasy Prospects, based upon over two months of baseball, including Spring Training and April games. The next update will be in two weeks on June 15th, including recent MLB draftees!

Since the beginning of May, several notable prospects exceeded rookie limits and others arrived in the majors. As this update only reviews performances for one month, please note this bright, flashing warning: SMALL SAMPLE SIZE!

Notable Catcher Prospect Performances

Since the publication of the 2018 Top 40 Fantasy Catcher Prospects, over four months passed, including Spring Training and two months of games. As such, there is significant movement in the top 40.

The Major League Catcher Prospect

The Graduate: Mitch Garver, Minnesota Twins. With Jason Castro out for the season, Garver is now the primary catcher for the Twins. Moving forward, he carries sneaky fantasy value with average power and a passable hit tool.

Chance Sisco, Baltimore Orioles. Remain patient with Sisco. Although he is struggling (.211/.318/.337 with 37.3% strikeouts), he flashes offensive potential with plenty of hard contact. Meanwhile, Sisco is performing better than expected behind the plate.

The Good

Zack Collins, Chicago White Sox. Arguably, Collins is the most extreme three-true-outcomes (home run, walk, or strikeout) player in the Minors. In 47 games, he has 52 walks (25.2%) and 54 strikeouts (26.2%). In May, Collins is performing the way the White Sox envisioned during the 2016 draft (.322/.508/.540). Despite his success, he continues to struggle against left-handed pitching (.195/.400/.195). As such, Collins is an ideal future platoon candidate and, as a catcher, it should not impact his fantasy value much.

Daulton Varsho, Arizona Diamondbacks. Although Varsho’s monthly performance at the plate was solid (.278/.364/.392), it does not rise to the level for inclusion here. On the bases, however, he went 9-for-9, raising his season total to 14 stolen bases!

M.J. Melendez, Kansas City Royals. Last summer, the Royals selected Melendez in the second round of the 2017 draft. A promising defender, he is showing his bat holds just as much potential. After a slow start to the month, Melendez exploded with 5 home runs (.284/.333/.579). Grade Change: power tool increases from 50 to 55.

Tom Murphy, Colorado Rockies. After an injury-plagued 2017 season, Murphy is back to mashing in Triple-A. This past month, he had 16 extra-base hits, including 8 home runs, though accompanied by 29 strikeouts. It will not be long before Murphy receives another shot in the majors.

Others of Note:

Danny Jansen, Toronto Blue Jays (.321/.434/.444)

Joe Trevino, Texas Rangers (.348/.400/.576)

Brett Sullivan, Tampa Bay Rays (.385/.433/.603 with 7 stolen bases)

Sicnarf Loopstok, Cleveland Indians (.284/.456/.522)

The Bad

Francisco Mejia, Cleveland Indians. Entering the season, many considered Mejia an elite hitter with several placing a 70-grade on his hit tool. Thus far, he continues to flounder in Triple-A, hitting just .192/.291/.301 in May. A switch-hitter, Mejia is struggling from both sides of the plate, but most significantly against right-handed pitching (.160/.237/.256).

Connor Wong, Los Angeles Dodgers. Despite a decent month on the surface (.223/.277/.394), Wong is swinging and missing at an alarming rate. Over just 24 games. he struck out 41 times (40.6%). On the year, Wong now has 70 strikeouts (38.5%) and 20.1% swinging strikes.

Alex Jackson, Atlanta Braves. Following a rebound season last year, Jackson reemerged as a relevant prospect. This year, however, has not been kind (.183/.270/.290). More recently, Jackson went 0-for-18 from May 7th to 11th and has 18 strikeouts in his last 10 games.

Eric Haase, Cleveland Indians. This year has not been a banner year for Indians’ catching prospects. In addition to Mejia, Haase struggled in May, hitting just .150/.181/.290 with an atrocious 34-to-4 strikeout-to-walk ratio.

Others of Note:

Jake Rogers, Detroit Tigers (.122/.205/.243)

Aramis Garcia, San Francisco Giants (.154/.185/.282)

Matt Whatley, Texas Rangers (.103/.159/.172)

Chris Okey, Cincinnati Reds (.095/.156/.095)

Additional Catcher Prospect Notes

The Cardinals promoted Andrew Knizner to Triple-A in mid-May. Meanwhile, Carson Kelly shares catching duties in the majors with Yadier Molina on the disabled list.

to Triple-A in mid-May. Meanwhile, shares catching duties in the majors with Yadier Molina on the disabled list. Will Smith has been on the disabled list since early May with an undisclosed injury.

has been on the disabled list since early May with an undisclosed injury. As a 19-year-old in Double-A, Keibert Ruiz is holding his own (.269/.321/.410), while limiting swing-and-miss (8.9 K%, 7.6 SwStr%).

is holding his own (.269/.321/.410), while limiting swing-and-miss (8.9 K%, 7.6 SwStr%). Rebound prospects Jacob Nottingham and Garrett Stubbs both spent time on the disabled list with minor injuries.

and both spent time on the disabled list with minor injuries. Victor Caratini is no longer a rookie, but he only has 124 at-bats. The Cubs just demoted him to Triple-A this week.

Notable First Base Prospect Performances

Since the publication of the 2018 Top 34 Fantasy First Base Prospects, over four months passed, including Spring Training and two months of games. As such, there is significant movement in the top 34.

The Major League First Base Prospect

Ryan McMahon, Colorado Rockies. Since returning to the majors last weekend, McMahon has a hit in all four games (5-for-17). Notably, he is filling in at second base for D.J. LeMahieu. With a strong showing, McMahon could push the struggling Ian Desmond out of a starting job.

Ronald Guzman, Texas Rangers. In his last 11 games, Guzman is 13-for-36 with 4 home runs, raising his slash line from .187/.253/.319 to a respectable .236/.307/.457. Standing at 6’5″ and 225 pounds, he has significant raw power and could surprise. With 127 at-bats, Guzman will shortly graduate.

Daniel Vogelbach, Seattle Mariners. An explosive May (.329/.465/.684 with 7 home runs) earned Vogelbach another brief promotion to the majors. Following the trade for Alex Colome and Denard Span, however, the Mariners shipped him back to Triple-A.

The Good

Cavan Biggio, Toronto Blue Jays. In the 90s, a lineup including names like Biggio, Guerrero, and Bichette would be formidable. Now, the next generation occupies the heart of the lineup for Double-A New Hampshire. This year, the son of Hall of Famer Craig Biggio, Cavan, shares the spotlight with Vlad Jr. and Bo. In May, he is not slowing down, hitting .327/.452/.673 with 9 home runs.

Matt Thaiss, Los Angeles Angels. One of the hottest players in the Minors, Thaiss hit .312/.386/.571 in his last 20 games in Double-A. Upon his promotion to Triple-A, he continued swinging a scorching hot bat (.308/.386/.667). On the month, Thaiss has 7 home runs. Notably, he inverted his batted ball profile, hitting far more balls in the air (44.6%) than on the ground (31.4%). This could be the beginning of a breakout.

Chad Spanberger, Colorado Rockies. A sixth round pick in the 2017 draft, Spanberger is a prototypical low batting average, power-hitting first base prospect. Luckily, he happens to play for the Rockies. In May, Spanberger hit .340/.383/.590 with 8 stolen bases. Much of his production comes at home (.382/.427/.742), where he enjoys one of the smallest parks in the country. Asheville’s McCormick Field is just 373 feet to center field, 320 feet to right-center field, and 297 feet down the right field line.

Nathaniel Lowe, Tampa Bay Rays. The older brother of teammate Josh Lowe, Nathaniel is truly breaking out this year. A patient hitter, he is finally tapping into his enormous raw power generated by his 6’4″ and 235 pound frame. Despite hitting .356/.442/.611 in May, Lowe actually lowered his overall line to .374/.451/.626. Turning 23 years old in July, he should receive a promotion to Double-A shortly.

Others of Note:

Peter Alonso, New York Mets (.284/.425/.510)

Jake Bauers, Tampa Bay Rays (.321/.400/.472)

Jake Gatewood, Milwaukee Brewers (.311/.353/.575)

Roberto Ramos, Colorado Rockies (.345/.439/.762 with 9 home runs)

Connor Joe, Los Angeles Dodgers (.367/.486/.611)

Taylor Jones, Houston Astros (.356/.469/.615)

The Bad

Brendan McKay, Tampa Rays. While McKay thrives on the mound, he is struggling to do anything at the plate other than walk (.192/.373/.288).

Nick Pratto, Kansas City Royals. Observers praised Pratto for his patient approach and advanced hit tool during the 2017 draft. This month, he posted a brutal 36-to-3 strikeout-to-walk ratio.

Sam Travis, Boston Red Sox. Since Travis returned from the disabled list (intercostal strain), he is 7-for-57 with 28 strikeouts (43.8%).

Mason Martin, Pittsburgh Pirates. Still just 18 years old, Martin received an aggressive assignment to Low-A after demolishing the Gulf Coast League last summer. Following a strong start this year, he hit a wall, going 3-for-44 with 23 strikeouts (46%) in his last 14 games.

Additional First Base Prospect Notes

Last weekend, Edwin Rios finally returned to action in Triple-A.

Notable Second Base Prospect Performances

Since the publication of the 2018 Top 32 Fantasy Second Base Prospects, over four months passed, including Spring Training and two months of games. As such, there is significant movement in the top 32.

The Major League Second Base Prospect

Gleyber Torres, New York Yankees. Although Tommy John surgery delayed his major league debut, Torres was worth the wait. Over the past month, he has been one of the best hitters in baseball, slashing .317/.374/.659 with 9 home runs. Even though the power output likely will come back to Earth, Torres has a special bat. Meanwhile, he has played every single game at second base and, with Didi Gregorius occupying shortstop, it appears second base is his home.

Others of Note:

Alex Blandino, Cincinnati Reds

Breyvic Valera, Los Angeles Dodgers

Luis Guillorme, New York Mets

The Good

Keston Hiura, Milwaukee Brewers. After a slow 15-game start (.180/.239/.279), Hiura closed April with a 9-for-23 finish. Since then, he kept hitting in May (.369/.430/.656). Meanwhile, Hiura finally debuted in the field, and has performed well at second base. Today, the Brewers promoted him to Double-A.

Nick Solak & Brandon Lowe, Tampa Bay Rays. Sharing second base and outfield duties, and batting back-to-back, Solak and Lowe are also both on fire. Once thought punchless, Solak is making the most of his modest power, hitting 6 home runs in May (.317/.430/.564). Meanwhile, Lowe posted nearly identical numbers to his teammate in May (.316/.440/.561). The dynamic duo provide a glimmer of hope for the Rays’ future.

Luis Garcia, Washington Nationals. Happy 18th Birthday, Luis! Just two weeks ago, Garcia turned 18 years old. His last day as a 17-year-old, he went 4-for-6 in a double-header. For the rest of the month, Garcia hit .371/.404/.526 as the youngest player in Low-A.

Bret Boswell, Colorado Rockies. Like Spanberger (above), Boswell enjoys the hitter-friendly confines of Asheville, where he is hitting .365/.385/.673 with 7 of his 8 home runs. Regardless, he had quite a month (.350/.384/.553) and power-hitting second basemen playing for Colorado are notable.

Others of Note:

Esteury Ruiz, San Diego Padres (.258/.357/.443 with 11 stolen bases)

Vidal Brujan, Tampa Bay Rays (.289/.400/.381 with 11 stolen bases)

David Bote, Chicago Cubs (.321/.418/.538)

Jonathan Arauz, Houston Astros (.325/.403/.521)

Luis Rengifo, Los Angeles Angels (.354/.451/.531 with 11 stolen bases)

Andy Ibanez, Texas Rangers (.333/.425/.567)

Jamie Westbrook, Arizona Diamondbacks (.264/.322/.555)

The Bad

Isan Diaz, Miami Marlins. Thus far in Double-A, Diaz is finding little success, including a poor May (.191/.329/.338). A three-true-outcomes slugger, he is mainly just striking out (28.5%) and walking (15.1%) this year.

Others of Note:

Luis Urias, San Diego Padres (.239/.357/.385)

Riley Mahan, Miami Marlins (.244/.327/.289)

Eliezer Alvarez, Texas Rangers (.153/.215/.250)

Josh Tobias, Boston Red Sox (.145/.194/.177)

Additional Second Base Prospect Notes

After a rough start transitioning to second base, Jahmai Jones has settled down, with just 3 errors in his last 28 games.

has settled down, with just 3 errors in his last 28 games. The Rockies promoted Garrett Hampson to Triple-A in mid-May, where he is experiencing some ups and downs (.241/.375/.397).

to Triple-A in mid-May, where he is experiencing some ups and downs (.241/.375/.397). The Braves officially moved Travis Demeritte to left field.

Notable Third Base Prospect Performances

Since the publication of the 2018 Top 36 Fantasy Third Base Prospects, nearly four months passed, including Spring Training and two months of games. As such, there is significant movement in the top 36.

The Major League Third Base Prospect

The Graduate: Miguel Andujar, New York Yankees. After an explosive April performance (.289/.302/.566), Andujar had a strong May (.290/.316/.430). Consistent hard contact has been a staple of his early performance. A free swinger, however, he remains among the league leaders in swing percentage (52.4%) and first pitch strikes (67.9%). With improved patience and a more lofted swing, Andujar could become a top fantasy third baseman.

The Graduate: Isiah Kiner-Falefa, Texas Rangers. With a Rangers infield decimated by injuries, Kiner-Falefa has received everyday playing time at second base and third base. A solid hitter with versatility, he should carve out a long-term utility role. Since Kiner-Falefa has just nominal power and average speed, he unlikely contributes much fantasy value.

J.D. Davis, Houston Astros. Following a dominant month in Triple-A (.470/.520/.773), Davis returned to the majors. Moving forward, he should see part-time action at first base and left field. With plus power and a hot bat, Davis could hit himself into a larger role.

Christian Arroyo, Tampa Bay Rays. Despite a sluggish start in Triple-A (.200/.235/.308), Arroyo “earned” a promotion in mid-May. Since he arrived, he has played part-time at second and third base. Although unspectacular, Arroyo is a potential plus hitter with modest pop.

Hunter Dozier, Kansas City Royals. An injury to Lucas Duda opened a path to playing time at first base for Dozier. Long held back by injuries, he finally may stick in the majors.

Others of Note:

Brandon Dixon, Cincinnati Reds

The Good

Vladimir Guerrero Jr., Toronto Blue Jays. The 19-year-old superstar is far too good for Double-A. This past month, Guerrero Jr. posted video game numbers, hitting .438/.480/.768 with 9 home runs. With the Blue Jays already 13.5 games back in the AL East, there is no rush to promote him. Nevertheless, expect Guerrero Jr. to debut later this summer.

Austin Riley, Atlanta Braves. An electric start in Double-A (.333/.394/.677) and a dominant four May games (7-for-15 with 2 doubles and 2 home runs) prompted the Braves to promote Riley to Triple-A. Upon his arrival, he kept mashing (.293/.347/.457), including a three-home run game on May 13th. Despite his success, Riley is notably struggling with strikeouts (34.7%).

Rylan Bannon, Los Angeles Dodgers. After blasting 8 home runs in April and another on May 4th, Bannon failed to homer again for over 3 weeks. Then, he hit home runs in 3 straight games from May 28th to 30th. Despite his reduced home run pace, Bannon still hit the cover off the ball this month (.340/.440/.567).

Others of Note:

Taylor Ward, Los Angeles Angels (.300/.410/.529)

Kelvin Gutierrez, Washington Nationals (.330/.379/.511)

Evan Mendoza, St. Louis Cardinals (.369/.440/.456)

Trevor Craport, Baltimore Orioles (.323/.383/.573)

The Bad

Nick Senzel, Cincinnati Reds. In May, Senzel missed nearly four weeks with vertigo. When he played (just 6 games), he struggled (4-for-21). As noted by Dr. Mike Tanner, “Senzel’s season ended prematurely last August due to vertigo” as well, and it could be a chronic problem.

Lucas Erceg, Milwaukee Brewers. A streaky hitter, Erceg has struggled mightily over the last month, going 13-for-111 between April 21st and May 24th. More recently, he is starting to turn it around, going 11-for-24 over his last 6 games.

Sheldon Neuse, Oakland Athletics. A breakout 2017 performance and a strong Spring Training elevated Neuse on prospect lists. The Athletics then aggressively assigned him to Triple-A, placing him on the cusp of a potential promotion. Since then, Neuse collapsed, hitting just .187/.250/.240 with 0 home runs and 73 strikeouts, including 46 strikeouts in May (43.4%).

Others of Note:

Tyler Nevin, Colorado Rockies (.192/.232/.346)

Cristian Santana, Los Angeles Dodgers (.238/.278/.327)

Dawel Lugo, Detroit Tigers (.240/.248/.300)

Andrew Bechtold, Minnesota Twins (.143/.212/.176)

Additional Third Base Prospect Notes

This month saw the return from injury of three third base prospects: James Nelson to High-A, Dermis Garcia to Low-A, and Matt Beaty to Triple-A.

to High-A, to Low-A, and to Triple-A. After a brief stint with the Rangers, Renato Nunez joined his second new organization this season and is now with the Orioles.

joined his second new organization this season and is now with the Orioles. David Thompson (fractured left hand) and Will Toffey (dislocated left shoulder) missed the entire month.

Notable Shortstop Prospect Performances

Since the publication of the 2018 Top 58 Fantasy Shortstop Prospects Part 1 and Part 2, nearly four months passed, including Spring Training and two months of games. As such, there is significant movement in the top 58.

The Major League Shortstop Prospect

The Graduate: Scott Kingery, Philadelphia Phillies. After an electric Spring Training performance, Kingery surprisingly received a six-year extension and made the Opening Day roster. A super utility man, he has received playing time (and now fantasy eligibility) at every position except catcher and first base. Recently, with J.P. Crawford on the shelf, Kingery has played out of position as the everyday shortstop. Given he is learning a new position at the highest level, he is struggling. In fact, Kingery is hitting just .222/.278/.322 while playing shortstop, which includes most of his dreadful May (.213/.263/.280).

Yairo Munoz, St. Louis Cardinals. The extended absence of Paul DeJong opened playing time at shortstop for Munoz and he is running with it. Indeed, he has a hit in each of his last 8 starts (14-for-32). A good hitter with pop, Munoz could surprise in a similar fashion to DeJong last year (with less power, of course).

Others of Note:

Franklin Barreto, Oakland Athletics (only coming off the bench)

Jose Rondon, Chicago White Sox

The Good

Fernando Tatis Jr., San Diego Padres. After Tatis’ terrible performance in April (.177/.231/.333 with 34 strikeouts), some began to question his hit tool despite being the youngest player in Double-A Texas League. A scorching hot May (.336/.414/.639 with 7 home runs and 5 stolen bases) has Tatis back on track.

Carter Kieboom, Washington Nationals. Like Tatis, Kieboom turned his season around in May (.391/.458/.576), with multi-hit games in 13 of his last 19 games.

Kevin Smith, Toronto Blue Jays. A fourth round pick in the 2017 draft, Smith displayed intriguing power (8 home runs) and speed (9 stolen bases) in his debut last year. A free swinger in college and his debut, he is showing much improved plate discipline this year. Meanwhile, Smith’s power/speed mix has led to 34 extra-base hits and 12 stolen bases in just 47 games, including a fantastic May (.379/.430/.705). Early this week, the Blue Jays finally promoted him to High-A.

David Fletcher, Los Angeles Angels. One of the biggest surprises of the season, Fletcher simply will not slow down, surprising with newfound power. Prior to this year, he had just 69 extra-base hits in 1,132 minor league at-bats. In his first 48 games this year at Triple-A (210 at-bats), Fletcher already has 33 extra-base hits! In fact, he already has 2 more doubles, 3 more triples, and 3 more home runs than he had in 111 games last year. This past month alone, Fletcher amassed 20 extra-base hits (.339/.395/.607).

Others of Note:

Brendan Rodgers, Colorado Rockies (.278/.322/.546)

Royce Lewis, Minnesota Twins (.317/.363/.465 with 10 stolen bases)

Nick Gordon, Minnesota Twins (.314/.378/.471, promoted to Triple-A)

Oneil Cruz, Pittsburgh Pirates (.323/.363/.516)

Nicky Lopez, Kansas City Royals (.367/.408/.458)

Kevin Newman, Pittsburgh Pirates (.361/.410/.435)

Santiago Espinal, Boston Red Sox (.346/.393/.580)

Manuel Geraldo, San Francisco Giants (.384/.413/.626 with 6 home runs and 11 stolen bases)

Richie Martin, Oakland Athletics (.379/.430/.563)

The Bad

Wander Javier, Minnesota Twins. After suffering a setback in recovery from a shoulder injury, Javier underwent surgery to repair a torn labrum. He is out for the season. Grade Change: increased risk from 35 to 30.

Cole Tucker, Pittsburgh Pirates. Following two months in Double-A, Tucker has yet to hit a home run and is an ugly 5-for-11 on the bases. Further, he is simply falling to do much at the plate, including an unsightly 2-for-40 stretch from April 25th to May 7th. Grade Change: reduced power tool from 40 to 35.

Isaac Paredes, Detroit Tigers. A strong April elevated Paredes into the top 200. Since April 28th, his season line fell from .282/.376/.521 to .217/.316/.373, including a 5-for-50 skid.

Others of Note:

Mauricio Dubon, Milwaukee Brewers (torn ACL, out for the season)

Aramis Ademan, Chicago Cubs (.203/.314/.257)

Kevin Merrell, Oakland Athletics (.255/.293/.282)

Gabriel Arias, San Diego Padres (.188/.266/.259)

Additional Shortstop Prospect Notes

Both Ryan Mountcastle (fractured right hand) and Domingo Leyba (shoulder surgery) debuted in Double-A this month and performed well.

Please feel free to post comments, questions, or your own observations!

Next Monday, the Monthly Prospect Update will explore outfield prospects. Stay tuned!

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