As the MLB season enters its crucial playoff phase, several rookies are stepping up to make significant impacts for their teams. Here’s a look at the top players you should consider adding to your fantasy baseball roster, including two standout pitchers who are making waves in their debuts.

Jonah Tong, SP, New York Mets

Jonah Tong, a 22-year-old right-hander, was recently promoted by the New York Mets and has already shown promise. In his debut against the Miami Marlins, Tong secured his first win, allowing only one earned run over five innings while striking out six. Known for his strikeout ability, Tong has punched out 162 batters in 102 innings at Double-A Binghamton and continued his dominance in Triple-A Syracuse. With the Mets experimenting with a six-man rotation, Tong has a clear path to more starts, especially as other pitchers like Tylor Megill and Clay Holmes face uncertainties.

Payton Tolle, SP, Boston Red Sox

Payton Tolle, a 22-year-old lefty, has been a revelation for the Boston Red Sox. Standing at 6-foot-6 and 250 pounds, Tolle’s fastball, thrown from a three-quarters slot, sits in the low 90s but plays faster due to his deceptive delivery. In his debut against the Pittsburgh Pirates, Tolle allowed just two runs over 5⅓ innings, showcasing his potential. With the Red Sox carefully managing his workload, Tolle is expected to remain in the rotation through the end of the regular season.

Sal Stewart, 2B/3B, Cincinnati Reds

Sal Stewart, a 21-year-old infielder, has been called up by the Cincinnati Reds to provide a spark to their struggling offense. Stewart has shown impressive stats in the minors, batting .306/.377/.473 in Double-A and .315/.394/.629 in Triple-A. With his low strikeout rate and patient approach at the plate, Stewart has the potential to make an immediate impact in the majors.

Carter Jensen, C, Kansas City Royals

Carter Jensen, a 21-year-old catcher, has been promoted by the Kansas City Royals following the trade of Freddy Fermin. Jensen posted a .288/.404/.647 line in Triple-A Omaha and is expected to see regular playing time against right-handed pitchers. While he may not be a top option in one-catcher leagues, Jensen is a solid pickup in two-catcher formats.

Connor Norby, 2B/3B, Miami Marlins

Connor Norby, returning from a hamate bone injury, has shown promise in his rehab games, recording a .353/.421/.765 line in Triple-A Jacksonville. The Marlins are expected to play Norby nearly every day down the stretch, giving him ample opportunity to prove his worth.

Jordan Lawlar, 3B/SS, Arizona Diamondbacks

Jordan Lawlar, a 23-year-old infielder, has been recalled by the Arizona Diamondbacks following the trade of Eugenio Suarez. Lawlar, who has struggled in his initial major league appearances, will get plenty of playing time this month as the Diamondbacks evaluate their future options.

These rookies and key pickups could be the difference-makers in your fantasy baseball playoffs. Keep an eye on their performances as the season winds down.