As the first half wraps up and we are left pondering who will flip the switch in the second half, it's only rational that we look at the players who have underachieved most.

We've already seen examples of players who have started to turn their luck around (Danny Jansen anyone?), so there is definitely credence in expected stats versus actual performance dictating possible regression. That doesn't guarantee it will happen of course, but it's certainly worth pondering for buy-low or add opportunities in leagues where you need a boost in the standings.

Rather than focusing on one category, I will list a few players in each major area that stands out and shows signs of still being fantasy-relevant.

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xBA Underachievers

All stats current as of July 7, 2019 and highlights players with at least 50 plate appearances this season.

-.051 BA-xBA in 232 PA

A week too late perhaps but we have to begin with Jansen, who has been mentioned previously in this column as an underachiever. He didn't appear destined to turn things around and had been one of the biggest draft-day busts at an already thin catcher position. Then a light bulb came on and Jansen caught fire, starting with a three-hit performance against the Yankees on June 26. That game included his third home run of the year.

Then he did it again. And again and again... Jansen hit six HR in a seven-game span, prompting those who had recently dropped him from their rosters to curse prodigiously. Power aside, Jansen finally brought his average above the Mendoza line, finishing the first half at .211. He still sits as one of the biggest underachievers compared to expected stats, so don't be surprised if this hot streak carries over.

-.034 BA-xBA in 159 PA

Why would we expect a high batting average from Seager in the first place? His BA has gone down each of the last three seasons, from a career-best .278 in 2016 down to .203 this year. We could blame the slow start on getting back into shape after missing all of April on the injured list but it's hard to excuse his .105 average in July.

Seager's .235 xBA isn't too promising either but we should pay attention to a 90.8 exit velocity that is a career-high and a 47.1% hard-hit rate that ranks 41st. If a few more balls starting falling in for him, he could be a nice source of RBI if he can stay in the sixth spot of the Mariners lineup.

-.033 BA-xBA in 297 PA

When digging for underachievers and buy-low assets, it's wise to start with the bottom-dwelling teams. The Giants have been miserable on offense, sitting at the bottom of the majors with a .231 team average and scoring the fourth-fewest runs. The optimist will point to an infusion of fresh blood such as Austin Slater, Mike Yastrzemski, and Alex Dickerson and say that better days may be ahead. The pessimist will simply skip this section and move onto younger, more exciting players while missing a potential opportunity.

Expected stats say Longoria should be batting .270 and slugging .490 on the year. His 9.1% walk rate is his best since 2013. Longo still has something left in the tank, proven by the fact his expected stats are all in the 67th percentile or higher. He won't be a league-winner but at an 18% ownership rate, he's worth an add as a power bat who won't go through prolonged slumps.

xSLG Underachievers

All stats current as of July 7, 2019 and highlights players with at least 50 plate appearances this season.

-.151 SLG-xSLG in 53 PA

Nate Lowe barely makes the 50 PA threshold for our purposes but is definitely worth mentioning. He still has a chance to be worth all that FAAB many owners paid upon his initial call-up a month ago. The rookie was sent down for a spell but came back up on Independence Day and has already made an impact, going yard twice in four games.

His late-blooming power is still very much in play for fantasy owners who need a boost. Lowe will be given every chance to wrestle away the regular spot as a lefty masher away from Ji-Man Choi. His lack of fortune in early at-bats could start to sway the other direction, making him a prospect to add now before everyone remembers what they were so excited for in the first place.

-.103 SLG-xSLG in 295 PA

The Smoak Monster has made more appearances in this column that any other player over the course of 2019. He just doesn't get enough credit, largely because he should be doing so much better. With 14 homers already and an expected slugging of .524, he should be a top-40 power option regardless of position. Also, forget power for a second - has anyone else noticed how he cut his K-BB% down to 3.1% this year???

Smoak is perennially uninspiring, which explains his 34% ownership rate across fantasy leagues. I can't promise any monstrous months ahead but as I've said before, don't be shocked if he ends up nearly matching his career-year numbers from two years ago.

-.072 SLG-xSLG in 329 PA

By all accounts, Turner is having a fine season. He is now slashing .294/.375/.446 with 10 HR, 34 RBI, 45 R. He could do even better in the second half though. His .446 SLG is the lowest since he moved to L.A. five years ago and Statcast says he should be 72 points higher. In fact, his xSLG is in the 86th percentile and his hard-hit rate is in the 82nd percentile despite a slow start to the year.

Turner isn't the type of player to crack 30 homers (27 is his career-best) but he is trending upward in the right ways and could be saving the best for late in the season.

xwOBA Underachievers

All stats current as of July 7, 2019 and highlights players with at least 50 plate appearances this season.

-.052 wOBA-xwOBA in 115 PA

"Underachiever" is an appropriate label for Pollock, especially in the fantasy realm. With an ADP of 118 ahead of the 2019 season, his draft price was at least more palatable before his inevitable injury. As a Pollock owner, if it makes you feel better, he was drafted right around the likes of Rougned Odor, Jurickson Profar, Aaron Hicks and Mike Foltynewicz. There are plenty of busts all around.

Pollock currently owns a career-low .223 average, paltry 7.8% walk rate and hasn't played since April because of an infection in his elbow. Now, the small bits of good news - he is on a rehab assignment as of July 4th and could return shortly after the All-Star break. His 90.5 exit velocity and 41.5% hard-hit rate are personal highs for him in the Statcast era. All his expected stats indicate positive regression is coming. This could make him a nice buy-low candidate while his price is depressed. Just make sure you have an extra IL spot handy, just in case.

-.040 wOBA-xwOBA in 219 PA

Aguilar is trying his best to get his name off this list, bopping two homers right before the break to reach eight on the year. *sarcastic cheer

Everyone and their mother will tell you they expected negative regression after his breakout 2018 season but we didn't know it would be this bad. Is he simply having bad luck and unable to get into a groove because his playing time has become inconsistent?

In short, no. His xBA is in the 25th percentile and his middling .335 xwOBA is in the 52nd percentile. Despite improving his walk rate to an impressive 13.2%, his .327 OBP is just not good because base hits have been few and far between. So he's getting what he deserves. The main thing that jumps out in his profile is the fact that he's faring far worse against fastballs this year (.235 BA), hitting almost 100 points worse than last year (.332 BA). It seems like a simple fix but we'll have to see it before believing in a turnaround.

-.040 wOBA-xwOBA in 359 PA

You didn't think J-Ram would avoid this list, did you? As I've said time and time again in this column, if not for the steals then Ramirez would be the biggest bust of the season. With a price tag of the third overall pick in most drafts, he's delivered a .218/.308/.344 slash line with seven HR, 35 RBI. By contrast, teammate Jason Kipnis is batting .240 with seven HR, 34 RBI.

While Ramirez's walk rate has dropped four points from last season's 15.2%, his batting average has dropped for two reasons: he's getting shifted more and he is focusing more on breaking balls. Some critics pointed out his .179 average versus breaking balls last year. Rather than letting that become an Achilles heel, he's upped it to .254 this season. In the process, his average has dropped 90 points (.211) versus fastballs. That can be corrected but he'll have to figure out how to beat the shift more frequently in order to get near his previous year levels of production.

Expect some improvement throughout the second half and a potential power binge at some point if he starts selling out for power but not to the point where he'll bring back the same return on investment you'd like.