6 Surprise MLB Breakout Stories from 2014 Crashing Back to Earth in 2015

Every year in MLB, there are breakout stars that come from nowhere and become household names with top-tier performances. Unfortunately, there always seems to be a handful of players who fail to live up to that success the following season.

2015 is no different, as multiple breakout players from 2014 are scuffling in the season's early months. 

Players such as Josh Harrison, Christian Yelich and Matt Shoemaker are just a few of the names who aren't seeing as much success after standout seasons a year ago.

There's a variety of factors that go into such a slip in production, and we'll try to put our finger on why each of the players on this list have crashed back to earth.

Steve Pearce

Associated Press

Steve Pearce has struggled with fastballs in 2015.

2014 Stats

.293/.373/.556, 21 HR, 49 RBI, .263 ISO, 161 wRC+

2015 Stats

.193/.265/.307, 3 HR, 11 RBI, .114 ISO, 57 wRC+  

The Skinny

Steve Pearce was a huge reason the Baltimore Orioles chose to not replace the departed Nelson Cruz and Nick Markakis this winter. 

Pearce played in 102 games for the O's last season, providing a huge lift to one of the league's top offenses. The 32-year-old launched 21 homers in 2014, and 47 of his 99 hits went for extra bases. Pearce actually led the Orioles in wRC+ and was second in WAR. 

2015 has been a different story for Pearce, as his numbers have plummeted well below the league average. Pearce is hitting fewer balls in the air this season, resulting in a significant drop in his fly ball-to-home run ratio.

Pearce's biggest issue is his lack of success against fastballs. He hit .322 against four-seam heaters in 2014 but has only managed a .186 average against the same pitch this season. Ryan Pollack at SB Nation reiterated that point in an article early this season. 

"This is Steve Pearce’s brand-new baseball game: one in which he sees more and more breaking and offspeed pitches," he said. "This is the adjustment opposing teams are making against him, one they’ve been making since 2012."

Pearce has recorded just four extra-base hits, and the Orioles offense is struggling without his production. Maybe he'll bounce back as the season enters the dog days of summer, but Pearce must adjust to a league that's clearly adjusted to him. 

Matt Shoemaker

Associated Press

Matt Shoemaker's seeing way more of his pitches leave the yard due to an increased fly-ball rate.

2014 Stats

16-4, 136 IP, 3.04 ERA, 3.26 FIP, 8.21 K/9, 1.59 BB/9

2015 Stats

3-3, 38.1 IP, 5.63 ERA, 5.58 FIP, 8.92 K/9, 1.64 BB/9 

The Skinny

Matt Shoemaker was one of the league's most pleasant surprises in 2014. 

In 20 starts, the right-hander finished the year second in WAR among Los Angeles Angels starters and posted a 3.04 ERA. Shoemaker combined swing-and-miss stuff with impeccable command to provide the Angels with another viable starter.

Shoemaker's strikeout and walk rates are nearly identical to his totals from last year, so what gives? 

For one, Shoemaker has stopped creating ground-ball contact. In 2014, opposing hitters hit the ball on the ground 41.2 percent of the time. 2015? Shoemaker's 22.8 percent rate is the lowest amount among major league starters with at least 30 innings of work. 

Looking at Shoemaker's pitch usage totals, he's completely abandoned his slider, which was his best ground-ball pitch a year ago. He's also throwing his changeup more than any other pitch in 2015, due to its massive success last season. But that increased usage has resulted in a near 80-point increase in opponent batting average. 

With more balls being hit into the air, Shoemaker has already allowed 11 homers after surrendering just 14 round-trippers in 2015. He seems to have lost confidence in the impressive mix of pitches he displayed last season. 

Devin Mesoraco

Associated Press

Devin Mesoraco's injured hip has sapped him of his power.

2014 Stats

.273/.359/.534, 25 HR, 80 RBI, .260 ISO, 147 wRC+

2015 Stats

.178/.275/.244, 0 HR, 2 RBI, .067 ISO, 47 wRC+

The Skinny

After a breakout season in 2014, the Cincinnati Reds inked catcher Devin Mesoraco to a four-year, $28 million contract this winter. 

Mesoraco has battled a hip injury in 2015 and hasn't caught a game since April 12, and it seems to be affecting his swing. Mesoraco's batting average has dipped below .200, and his on-base percentage has fallen below the .300 mark. 

Mesoraco's problems are fairly simple—he's just not hitting the ball hard. His line-drive rate has fallen from 22.9 percent to 13.9 percent, and he's popped up over 25 percent of the time. After making medium or hard contact 88 percent of the time in 2014, Mesoraco's soft contact has increased to a 33.3 percent mark. 

Mark Sheldon of MLB.com has reported that Mesoraco is considering surgery on his hip. 

"That's kind of the time," Mesoraco told Sheldon. "We have to see if it's going to work out. It's been over a month [since catching]. If it's going to work, it's going to happen at that time. If it isn't, we'll know at that time. At this point, it's time to figure it out."

His hip issues would explain a significant lack in pop in 2015. Whatever the reason, Mesoraco has had a nightmare season after signing his contract this offseason. 

Adam Eaton

Associated Press

Adam Eaton has struggled to live up to his new contract.

2014 Stats

.300/.362/.401, 76 R, 15 SB, 115 wRC+

2015 Stats 

.234/.286/.343, 19 R, 1 SB, 72 wRC+

The Skinny

The Chicago White Sox were proactive in signing Adam Eaton to a multiyear deal as well this winter. 

Eaton hit .300 with an above-average on-base percentage for the White Sox last season. He also stole a handful of bags and saved 12 defensive runs in center field. 

The 26-year-old hasn't been as fortunate through the season's opening weeks. Eaton's OBP has fallen below .300, and he's stolen only one base in 33 games. 

Eaton's infield hit percentage has seen a significant dip from over 12 percent to 6.2 percent, and he's popping up an alarming 24 percent of the time. That's the second-highest mark in all of baseball. 

The 26-year-old admitted to CBS Chicago's Bruce Levine that his new deal may have been a distraction. 

"

It is human nature. You sign a contract and with all the new faces in here, I wanted to prove to them I was worthy of leading off at the top of a very good batting order. I want the others like Jose (Abreu) to have a great year. In order for them to do that, they need to have men on base. That is my job. I take it very personal when we don’t have a lot of hits starting off. When it starts to rumble the wrong way, sometimes I try harder than I should. After a couple of wins, I can fall into place and get the job done.

"

Eaton has played better in May, slashing .288/.344/.458 in 14 games. He's a key cog in a White Sox offense that could definitely use a spark and will be vital to any success the team has in 2015. 

Christian Yelich

Stephen Dunn/Getty Images

Christian Yelich is striking out more than he did in 2014.

2014 Stats

.284/.362/.402, 9 HR, 94 R, 52 RBI, 21 SB, 116 wRC+

2015 Stats

.179/.266/.238, 1 HR, 6 R, 6 RBI, 4 SB, 44 wRC+

The Skinny

The Miami Marlins obviously bought into Christian Yelich's 2014 campaign, as the Fish shelled out over $49 million over seven years to lock down their talented young outfielder. 

Yelich's strikeout percentage has seen a near 8 percent increase from 2014 to 2015. His contact percentage has fallen over 10 percent, and he's chasing pitches outside the zone more than he did a season ago. 

When he does make contact, Yelich is hitting the ball on the ground more than anybody in baseball with 40 plate appearances. With an abundance of grounders and above-average speed, a case could be made that Yelich's .250 average on balls in play is a tad unlucky. But a significant drop in line-drive rate has also weighed into that mark. 

Yelich has spent time on the disabled list with a bulging disk in his back, but it's no coincidence the Marlins are struggling without a productive Yelich. His average should start to rise, and he'll likely begin to see some better luck on balls in play. 

Without him, Miami won't be able to recover from its poor start to the campaign. 

Josh Harrison

David Banks/Getty Images

Josh Harrison has swung the bat better in May, but he's failed to live up to his breakout 2014 so far this season.

2014 Stats

.315/.347/.490, 13 HR, 52 RBI, 77 R, .175 ISO, 137 wRC+

2015 Stats

.255/.289/.407, 4 HR, 11 RBI, 20 R, .152 ISO, 92 wRC+ 

The Skinny

An argument can be made that Josh Harrison was the biggest breakout star in baseball last season. He finished in the top 25 in baseball in WAR, wRC+ and batting average in 2014. 

Harrison hasn't enjoyed the same success in 2015. His average has dropped to a .255 mark, and his on-base percentage has dipped under .300. 

There's been a significant change in Harrison's BABIP between 2014 and 2015. He hit .353 on balls in play last year but has seen that number fall to .277 this season. Harrison is making more soft contact than he ever has in his career, which would explain why his BABIP has plummeted. 

Harrison is also pulling the ball much less than he did last season. Joshua Choudhury of SB Nation believes that has resulted in a decline in the quality of line drives and fly balls Harrison is hitting:

"

The point here is that the quality of the fly balls and line drives Harrison is hitting hasn’t substantively declined between 2014 and 2015. He hit .165/.624 (BA/SLG) on fly balls in 2014, and he’s hitting .160/.560 on fly balls in 2015. He hit .677/.977 on line drives in 2014, and he’s hitting .455/.682 on line drives in 2015.

"

Harrison has flashed signs of better swings as of late. He's slashing .308/.338/.462 with six extra-base hits in May. His aggressive attitude at the plate is always going to lead to streaky luck on balls in play, so Harrison might be on the verge of some good fortune. 

Advanced stats courtesy of FanGraphs. 

Stats accurate as of May 21.