National League rookies to watch beyond Pirates SS Konnor Griffin

The most talked-about prospect in all of Major League Baseball is Pittsburgh Pirates shortstop Konnor Griffin, who is only 19. 

At 6-foot-3 and 222 pounds, Griffin has a commanding presence and impressive power. In his first six spring training games, he blasted three home runs and drove in six. Two of those home runs came against the Boston Red Sox at JetBlue Park on Feb. 24. 

Griffin put together a fantastic 2025 season, batting .333 with an OPS of .941 and 21 home runs in 122 games on three levels in Pittsburgh's organization. 

But Griffin isn't the only rookie who could shine in the National League this season. Here are five more: 

Starting pitcher Nolan McLean | New York Mets | MLB prospect ranking: No. 6

After debuting — and impressing — in his first eight starts (5-1 with a 2.06 ERA) in the big leagues in 2025, right-hander McLean will enter his first full season in MLB as a No. 2 starter behind ace right-hander Freddy Peralta. With a nasty sweeper and an electric fastball, McLean has made one start in the spring, striking out six in four innings. 

OF Justin Crawford | Philadelphia Phillies | MLB prospect ranking: No. 53

In 2025, Crawford stole 46 bases (caught 11 times) in the International League (Triple A). Crawford was also a hitting machine last season, batting .334 and posting 147 hits in 440 at-bats (506 plate appearances). 

Crawford is having a fantastic spring training, batting .316 with three doubles in six games, and could be the starting center fielder on Opening Day. Crawford’s best asset at the plate is his ability to bunt, a lost art in baseball.

Infielder Sal Stewart | Cincinnati Reds | MLB prospect ranking: No. 22

Stewart, like McLean, spent 18 games in the big leagues last season, batting .255 with an OPS of .839 and five home runs. At Double A and Triple A, Stewart proved to be an all-around hitter, posting 34 doubles and 20 home runs and a .309 batting average. 

Stewart has gone off this spring, batting .429 with a .929 OPS and two home runs (five RBI) in six games, and will likely be the starting third baseman despite the addition of third baseman/designated hitter Eugenio Suarez in free agency.

Starting pitcher Andrew Painter | Philadelphia Phillies | MLB prospect ranking: No. 28

Painter, who is two years removed from having Tommy John surgery, struggled with his command last season at Double A and Triple A. In 118 innings, he went 5-8 with a 5.26 ERA, 47 walks and 20 home runs allowed. Painter has only made one start this spring, but he did well in his two innings, punching out one and walking none. 

Painter will replace left-hander Ranger Suarez in the starting rotation — Suarez signed a five-year, $150M contract with the Boston Red Sox in the offseason — and will log more innings in the spring with his teammate, right-hander Aaron Nola, departing to pitch for Italy in the World Baseball Classic. 

Outfielder Owen Caissie | Miami Marlins | MLB prospect ranking: No. 42

Caissie, the centerpiece in the trade that sent right-hander Edward Cabrera to the Chicago Cubs, should be the starting right fielder in 2026. Caissie joins an intriguing outfield featuring All-Star left fielder Kyle Stowers (.288 BA, 25 HRs in 2025) and center fielder Jakob Marsee (.292 BA, 14 stolen bases in 2025). 

Caissie has struggled this spring, hitting .111 and striking out six times in nine at-bats (four games), which could lead to a demotion to Triple A. If demoted, outfielder Griffin Conine would be the right fielder, as he was before undergoing a season-ending shoulder surgery in April 2025.