5 surprising difference-makers from first half

There aren't many surprises left at the All-Star break. The hot starts at the beginning of the season have fallen away and everything is shaping up more or less as you expected it -- i.e., Mike Trout is near the top of every leaderboard imaginable.
But some surprising players never cooled down. For these five players, their second-half performance won't just be compared to their hot start, but it will have a big impact on the pennant races. Can they keep performing and help their team to October? Or will they regress back to former levels, leaving a hole on the roster along the way?
1. Marcell Ozuna, OF, Marlins
.307/.360/.533, 17 home runs, 47 RBIs, 136 wRC+
Expected to break out in 2015, Ozuna saw his numbers dip so low he was eventually demoted to Triple-A New Orleans. Looks like the breakout came a year late. With Giancarlo Stanton struggling through the early part of the year, Ozuna is a big reason the Marlins are tied with the Mets for the second National League Wild Card spot.
Can Ozuna keep it up? Not only does he absolutely crush the ball every time he connects, but he's picked up a new skill this season, too. After struggling with pitches low and away in 2015, Ozuna's average exit velocity is way up on those pitches and, predictably, his average on them is, too.

2. Jay Bruce, OF, Reds
.267/.315/.538, 18 home runs, 63 RBIs, 118 wRC+
Bruce was too talented not to bounce back. Sure enough, the 29-year-old outfielder has rebounded from a .222/.288/.406 line in 2014-15 to put up numbers remarkably similar to his previous career norms. The hot start has made Bruce a top target for contenders in need of outfield help like the Indians, Dodgers and Nationals.
Can Bruce keep it up? If a move away from the homer-friendly confines of Great American Ball Park is in the cards, then his new-found ability to hit for power to the opposite field could prove important. After hitting zero home runs to left field last season, Bruce has hit five in 2016.

There is one concern for the always streaky Bruce, though: His average exit velocity has dropped below league average for the past three weeks. Over that time, he's hit a meager .234/.263/.429.
3. Jackie Bradley Jr., OF, Red Sox
.296/.378/.548, 14 home runs, 55 RBIs, 140 wRC+
The way Bradley goes, so go the Red Sox. While obviously an oversimplification, when he was hitting .331/.409/.601 over the first two months, Boston was 32-20 and had a three-game lead in the American League East. Since then, Bradley hit .244/.336/.479 and the Red Sox stumbled to a 17-18 mark and are now two games back of the Orioles.
Can Bradley keep it up? While he has a proclivity for slumps, he kept his power production up during his recent cold spell -- something he failed to do in the past. Bradley will need to watch out for trying to hit home runs though, as his fly-ball rate skyrocketed in June. He may have already course corrected and entered the break on a six-game hitting streak.
4. Tyler Naquin, OF, Indians
.314/.374/.591, 9 home runs, 22 RBIs, 155 wRC+
The Indians' rotation is so strong, they could possibly win the presidential election as a group ticket. To win the World Series though, they'll need offense. With Michael Brantley's injury status still uncertain, Naquin has proven to be a salve in center field since being recalled at the beginning of June.
Can Naquin keep it up? Unfortunately, his 29.5 percent strikeout rate and .418 BABIP are poor bets for him to continue hitting at a Manny Machado-like rate. As a left-handed bat, Naquin could prove an important depth option or even a platoon partner for Clint Frazier if the Indians call up the top prospect for the postseason push.

5. Rich Hill, LHP, A's
   9-3, 2.25 ERA, 10.66 K/9, 3.32 BB/9
   Entering last year, Hill was a 35-year-old nearly-constantly-injured reliever who hadn't topped 38 2/3 innings in a season since 2009. One change to an arm slot later, and while throwing his looping curveball just under 50 percent of the time, he's become the second coming of Clayton Kershaw.
   Let's compare the two.
   Hill since 2014: 2.06 ERA, 203 ERA+, 10.8 K/9, 2.8 BB/9
   Kershaw since his first National League Cy Young Award in 2011: 2.08 ERA, 176 ERA+, 10 K/9, 1.8 BB/9

Can Hill keep it up? That's the question teams will be asking for the next three weeks as trade talks for the A's pitcher heat up. There are few players like Hill who rely so much on an offspeed offering -- especially without a blazing fastball to play off of it -- so while his recent success certainly seems sustainable, we're really just along for the ride, too.