Who are the players to watch in the National League Central this month?

It might be a star coming out of a slump, like Kris Bryant. Or a key player returning from an injury, like Starling Marte. Sometimes the player to watch is just the one you can’t take your eyes off of, like Christian Yelich. But even within a five-team division, each club has different needs and specific players it's counting on one month into the season.

Here’s a look at one player to watch in May for each NL Central team.

Brewers: Christian Yelich

Obviously, right? Yelich is the reigning NL MVP Award winner, and he’s coming off a 14-homer start to the season in which he and the Dodgers’ Cody Bellinger matched the all-time record for home runs before May 1. (For the trivia buffs out there: They tied Albert Pujols in 2006 and Alex Rodriguez in '07.)

Besides being such a watchable player by default, Yelich entered the month of May on the sidelines with a tight back, an ailment similar to the one that cost him a handful of games late last June and early July. When he returned from that rest, Yelich caught fire, hitting a home run in the All-Star Game that propelled him into Major League Baseball’s most productive second half and the NL MVP Award. If the side effect of the unexpected break that he’s currently on looks anything similar to last season's, Yelich could be in for another power-packed month.

Cardinals: Andrew Miller

Brought in to be the bullpen kryptonite against some of the game’s most potent left-handed bats, Miller is set to be tested over the next month. With six games apiece against both the Braves and Phillies, Miller will be needed to oppose the likes of Freddie Freeman and Bryce Harper. The Cardinals also have four May games against Anthony Rizzo’s Cubs and three vs. Joey Gallo’s Rangers.

All of that means Miller will likely appear in several key late-inning spots, and his success could make or break the Cardinals’ bullpen blueprint. The good news for the Cards is that Miller closed April on an upswing by allowing one baserunner in his final three appearances combined. Lowering his walk rate -- which was 7.15 per nine innings in April -- and finding a feel for his slider should help keep Miller trending in a positive direction.

Cubs: Kris Bryant

Bryant’s offensive production in March and April was better than average. He entered May with a 102 adjusted OPS+ and a 110 wRC+. But the Cubs have come to expect more than just “above-average” performance from their star slugger, and they’ll need him to help carry their lineup as they play 13 games against NL Central opponents, as well as four against the Phillies, three in Washington and three in Houston.

The good news is that Bryant may have turned a corner as the Cubs flipped the calendar to May. He went deep twice in three games against the D-backs last weekend and he ended April on a four-game hitting streak, boosting his slugging percentage from .366 to .420 during that stretch. It also bodes well that Bryant has been taking his walks, drawing 15 free passes while only striking out 22 times in his first 26 games. It seems like a matter of time before Bryant gets hot.

Pirates: Starling Marte

How important is Marte to the Bucs’ success? Just look at their record. After he clubbed a key two-run homer in his first game off the injured list on Tuesday night, they were 12-5 when he played and 1-9 when he didn’t. And it wasn’t even a good month, offensively, for Pittsburgh’s center fielder. He ended an injury-interrupted April with a .197/.230/.394 slash line, 16 strikeouts, one walk and only two steals.

But Marte -- who hit a career-high 20 homers and stole 33 bases last season -- offers upside for a Pirates lineup in need of another dynamic threat alongside slugging first baseman Josh Bell. He’s also a valuable defender in center; starter Trevor Williams joked that Marte already locked up an NL Gold Glove Award with a nine-putout game in Washington on April 12. Pittsburgh tends to go as he goes, so if he gets hot at the plate, maybe the rest of the team will follow suit.

Reds: Sonny Gray

Gray has joined with ace Luis Castillo to give the Reds a nice 1-2 punch at the top of the starting rotation. Despite having a 3.64 ERA, Gray is 0-4 over his six starts and the club is 2-4 when he pitches as the offense has struggled to score runs for him. In four of his outings, Gray has essentially been undone by the one rough inning that cost him.

Although he struggled at home when with the Yankees in 2017-18, Gray has pitched well at Great American Ball Park and he has not given up a home run there. Hitters are batting .198 against him overall, and he’s given up only eight walks while striking out 36 batters. If he can get more run support while fine-tuning his performance, Gray could return to the form that made him an All-Star for the A’s in 2015.