This week, I’m focusing on the most and least valuable hitters and pitchers through the first half of the MLB season. To do this, I define “value” based on how well a player has performed to date and compare it to their average ADP (average draft position). For example, Mookie Betts has been phenomenal in 2018, but he was also drafted inside the top 10, so, unfortunately, he won’t be considered in this piece. As far as the least valuable players go, I will exclude major injury as a reason for low value which excludes guys like Josh Donaldson. The All-Star break is right around the corner. It’s a good time to reflect on the first half of the season.

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Who is the most valuable fantasy hitter in the first half?

I took a look at players like Javier Baez, Eugenio Suarez, and Eddie Rosario who are all having fantastic seasons and are outperforming their ADP by over 100 spots. However, each and every one of these players were drafted in all leagues and had shown improvements in 2017 from previous years. The hitter I believe has been most valuable to fantasy owners is a guy whose ADP per NFBC was 477! That means, he likely wasn’t drafted in any 10-, 12- or even 15-team leagues. As of Tuesday, this player’s ranking on the ESPN Player Rater is No. 39 overall. That’s a difference of 438 spots between his ADP and current ranking.

This is Jesus Aguilar, the first baseman of the Milwaukee Brewers. Aguilar is currently hitting .305 with 23 home runs and 64 RBI in only 285 plate appearances. It’s not that Aguilar hasn’t shown power before. Last year he hit 16 homers in just over 300 plate appearances in his age-27 season. That is about a 30-HR pace over the course of a full season. Aguilar is a classic slugger who strikes out a bunch, hits the ball extremely hard, and pulls a good portion of his fly balls.

The difference with Aguilar in 2018 is twofold. One, he’s cut his strikeout rate by nearly four percent and two, he’s significantly improved his launch angle from 11.8 degrees to 17.8 degrees. His ground-ball rate is down nearly 11% without sacrificing hard contact and reducing his infield fly-ball rate. To start the season, Aguilar had playing time issues with Eric Thames at first base and Ryan Braun getting reps there as well. The outfield was also overcrowded with the additions of Lorenzo Cain and Christian Yelich. It’s understandable why Aguilar was left for dead on draft day. With his performance along with the demotion of Domingo Santana and several DL stints (mostly from Braun), Aguilar is here to stay, but be aware of his poor plate discipline. It would be foolish to expect the current pace to continue, but crazier things have happened.

Honorable Mention: Max Muncy (LAD)

Who is the most valuable fantasy pitcher through the first half?

Off the top of my head, I thought of All-Star snub Blake Snell as a candidate for the most valuable pitcher through the first 82 or so games. Snell is ranked seventh among starting pitchers on the ESPN Player Rater and 15th overall! His NFBC ADP was just outside of the top 200 at 201. Snell’s number one contender, Ross Stripling is ranked 56th overall and the 19th starting pitcher on the ESPN Player Rater but was drafted with an ADP of 493. That’s just after Jesus Aguilar. With all due respect to Mr. Stripling, a top seven starting pitcher is an ace in fantasy leagues and those are not easy to come by. My pick is All-Star snub, Blake Snell.

Snell was a popular sleeper after showing improvements in the second half of 2017. He’s improved on his strikeout rate, walk rate, zone contact, four-seam velocity, and most significantly LOB%. Yes, an 88% LOB rate is not sustainable. I’m amazed he’s maintained that high of a rate at this point in the season. That ranks highest in all of baseball among qualified starters and is three percentage points higher than Jacob deGrom who is second. His .234 BABIP is fourth lowest in the league but the Rays do possess a very good defensive outfield and Snell gives up 37% fly balls.

The new ace of the Tampa Bay Rays may have some luck on his side, but he has two pitches with insane numbers against. His curveball is so good, opponents are only hitting .138 against it with an UNLUCKY .343 BABIP! That’s because Snell has a 58% K rate with the pitch and a two percent walk rate. For those of you at home, that’s a 56% K%-BB% or a 29.0 K/BB ratio. Anything over four is very good. His slider has similar success with a 47% K rate and a nearly 27% Swing strike rate. Opponents are hitting only 0.095 against the slider. Snell might be a little lucky but with two pitches that are as good as his breaking pitches, I believe in his success. I think there’s some regression coming, but believe in Snell as a top 15 starting pitcher the rest of the way. That’s quite a draft day steal.

Honorable Mention: Ross Stripling (LAD) and Trevor Bauer (CLE)

Who is the least valuable fantasy hitter?

Kris Bryant is not having a very good year, but he’s also been on the disabled list for almost a month. I believe he was dealing with the injury for a significant amount of time prior to the DL stint. Bryant does not qualify, so my least valuable hitter to date is Brian Dozier. Per NFBC, he was drafted with an ADP of 39th overall and currently sits at 195 overall per the ESPN Player Rater. He has not been hampered with injuries, he’s just struggled through the first half of 2018. This is nothing new for Dozier. In 2016, Dozier hit .246 with 14 homers in the first half and in 2017, he hit .242 with 13 homers. With a home run last night, he now is hitting .225 with, you guessed it, 14 home runs.

Dozier has averaged nearly 25 home runs in the second half the last two seasons, why should this year be any different? Thus far, Dozier is hitting the ball harder by 2.5% and is hitting a few more fly balls. However, it’s at the expense of line drives which explains his low BABIP. His home run rate, however, is down six percent while his pull percentage matches last year’s rate. There are a couple factors here. First, check out Alex Chamberlain’s piece on FanGraphs highlighting how hard contact and launch angle have improved league-wide this year, but home runs are down. Basically, it explains how the ball may have been de-juiced this year. Meaning, Dozier’s hard-contact and flyball rate improvements aren’t netting him any gains.

Dozier has picked it up of late, and I’m betting on a bounce back in the second half but not to the extent it’s been the last two years. His high drive percentage is down three percent while his popup rate is up nearly seven percent. Dozier made more strides in the second half of 2016 compared to 2017. If you’re expecting 20+ homers in the second half from Dozier, I’d closely monitor his hard contact, flyball rate, and pull percentage which should be in the vicinity of 40%, 50%, and 55%, respectively. He’s most likely going to be a .250 hitter with 12 to 15 homers the rest of the way with a handful of steals.

Honorable Mention: Jonathan Schoop (BAL)

Who is the least valuable fantasy pitcher?

Yu Darvish, Clayton Kershaw, Robbie Ray, and Chris Archer have all performed well below their expectations but most of their value has been lost due to injuries. Luis Castillo was a super popular sleeper coming into 2018 who was over-inflated. I am guilty of believing in Castillo as a potential top-20 starting pitcher coming into the season. I will probably be back in next year if he makes successful second-half improvements. The hype was warranted based on an 89-inning sample in the second half of 2017. Anytime a pitcher throws 97 mph with a wipeout slider and an elite swing-and-miss changeup, fantasy analysts get excited.

What a change a year makes as we sit here on July 11th. His ERA is an unsightly 5.58 after closing 2017 with a 3.12 ERA. There has been regression in his K%, HR/9, BABIP, ground-ball rate, and LOB%. With hindsight being 20/20, his 12.2% line drive from 2017 should have been a red flag. That is simply not sustainable. His four-seam fastball has lost almost two mph from 2017 but it’s his sinker that has been a complete punching bag. Opponents are hitting an insane .371 off the sinker with a .608 slugging and have blasted six home runs on a total of 367 pitches thrown! It no longer can produce an extremely elevated ground-ball rate which is down 14% from last year effectively limiting its value.

Ok, enough bashing. The good news for Castillo owners, the few that re left, is that his secondary offerings are actually better than last year. His changeup has a 43% K rate and a 26.7% swinging strike rate. His slider has also been excellent with well above average O-Swing, Z-Contact, and SwStr%. Castillo has to iron out his issues with the sinker/four-seam combination in order to succeed, but he’s not far off from coming back to a mid-three ERA pitcher with a 9+K/9. If you’ve held him this long, you may want to wait until after the All-Star break to see if he’s made adjustments. If he’s available in your league, try to grab him as a flier. If nothing else, he has upside.

Honorable Mention: Jose Quintana (CHW)

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Max Freeze is a correspondent at FantasyPros. For more from Max, check out his archive and follow him @FreezeStats.