What to expect from Mets prospect McLean in the big leagues

This Saturday, a new delectable item comes to Citi Field: Nolan McLean sliders.

The Mets are calling up MLB Pipeline’s No. 37 overall prospect to make his Major League debut with a home start this weekend against the Mariners, MLB.com’s Anthony DiComo reported Wednesday.

Ranked as the top pitching prospect in New York’s system, the 24-year-old right-hander owns a 2.45 ERA and 1.13 WHIP with 127 strikeouts in 113 2/3 innings with Double-A Binghamton and Triple-A Syracuse this season. Since joining the Minors’ top level in early May, he has a 2.78 ERA in 16 appearances (13 starts) in the International League, and his 27.0 percent strikeout rate ranks seventh among 51 pitchers with at least 80 Triple-A innings in 2025.

Since July 1, McLean leads the Minor Leagues with 52 strikeouts, fanning at least six in each of his seven outings (six starts) in that spell.

Taken in the third round of the 2023 Draft as a two-way player out of Oklahoma State, the 6-foot-2 hurler has flourished in his first full season fully focusing on pitching.

McLean’s trademark pitch is a monster 84-87 mph sweeper that averages 15.4 inches of gloveside movement and 2,872 rpm. It was his most-thrown pitch in Triple-A – it helps that he throws his mid-90s sinker and four-seamer almost equally, splitting his fastball usage – while opponents batted just .187 against it with a 30.1 percent whiff rate. Only Will Warren, Dustin May and Taylor Rogers have thrown sweepers with that much sweep and that high a spin rate in the Majors (min. 300 sweepers thrown).

Throwing from a lower three-quarters arm slot, McLean tends to lean on the sweeper-sinker combo against righties with the latter pitch breaking around 16 inches armside, essentially mirroring the break of the sweeper and giving same-side hitters a wide horizontal zone on which to focus. Such an approach leads to a ton of groundballs; McLean’s 54.7 percent groundball rate is seventh-best among full-season Minor League qualifiers this year.

He’ll still use the sinker and sweeper against lefties too, but he’s more likely to fold in that four-seamer (which touched 97.7 mph with Syracuse) to incorporate more ride up in the zone, though the movement profile isn’t great. He also mixes in an 88-90 mph cutter that actually gets a tiny bit of armside movement and a 78-80 mph curveball that regularly exceeds 3,200 rpm and gets 18-19 inches of sweep and 57 inches of drop. He’s only gone to the deuce around one-eighth of the time against lefties, but those hitters missed on 42.9 percent of their swings against the curve in Triple-A.

McLean has an 85-88 mph changeup but treats it like a fifth pitch since it’s the offering he most often throws for a ball (around 49 percent of the time, per Synergy Sports).

As might be expected, the former Cowboy can run into pretty severe splits issues; righties have hit .153/.244/.211 against him over 235 plate appearances in 2025 while lefties have produced a more robust .232/.341/.364 line in 232 PA. His 10.6 percent walk rate with Syracuse was also a smidge below Triple-A average (10.9), but that control will be tested against more patient Major League hitters.

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McLean could run into trouble against lefty-heavy lineups in The Show -- a reason why Seattle could make for an interesting first opponent with switch-hitters Cal Raleigh and Jorge Polanco flipping to that side -- but the Mets’ newest starter could still provide a unique look for even veteran MLB bats given his incredible feel for spin.

With the Mets ceding ground to the Phillies in the NL East, it’s time to see if the best arm on the farm could help them find steadier footing in Queens.