NY Mets rookie Nolan McLean is off to a historic MLB start

The New York Mets called up top right-handed pitching prospect Nolan McLean to make his MLB debut on August 16. Expectations for McLean were high, given he performed well at Triple-A with a 2.78 ERA and 27.2% K%, and is ranked as a top 40 prospect by MLB Pipeline (#36) and Baseball America (#39). But the start of his career is the best the Mets have ever seen in their franchise history, even better than one of the best pitchers of all-time, Mets legend Tom Seaver.

McLean has pitched 26.1 innings through his first four Major League starts. In that time, he has a microscopic 1.37 ERA, 2.41 FIP, and 0.76 WHIP. McLean is getting plenty of strikeouts, with a K% just a shade under 30%, clocking in at 29.5%. On top of that, he is walking batters at a low rate, with a 7.4% BB%. Home runs haven’t been an issue for McLean either, as he has allowed just a single home run thus far.

But McLean is even outperforming Tom Seaver when looking at their first four starts in 1967. Seaver pitched a similar amount of innings, with 28.2 IP, while posting a 1.83 ERA, 2.43 FIP, and 1.08 WHIP. Seaver was striking out batters at a 17.2% rate, which was 1.6% better than league average. He did have a lower walk rate than McLean, however, with a 5.2% BB% when the league average was 7.9% (league average is 8.4% in 2025). Seaver also allowed just one home run through his first four outings.

Nolan McLean is pitching at a level the NY Mets have never seen before.

McLean isn’t just outperforming Seaver in ERA, but he is outperforming every Mets rookie starting pitcher, at least through their first four outings. According to Marc Webber on Twitter/X, McLean’s 1.37 ERA is the lowest ever in the franchise’s history. The next closest is Jim McAndrew with a 1.82 ERA throughout his first four starts in 1968, one year after Seaver. Noah Syndergaard also had a 1.82 ERA in 2015, and Steven Matz had a 1.88 ERA to kick his career off, like Tom Seaver.

That means that no Mets pitcher has ever had a sub-1.50 ERA through their first four starts of their career. Only 33 pitchers since the turn of the millennium have put up an ERA just as low or lower than McLean’s through their first four starts with at least 20 IP. This includes some outstanding pitchers from the late 2000s and the 2010s, like Felix Hernandez and Jered Weaver. It is also worth noting that McLean's 28 K's is the third most by a rookie pitcher in their first four starts since 2000 while carrying an ERA of 1.37 or lower, surpassed by King Felix (30), and Tanner Houck (29).

Four starts and less than 30 innings pitched isn’t the largest sample size, but Nolan McLean couldn’t ask for a better start to his Major League career. He is performing at a level the Mets have never seen from a rookie to start a career. The way McLean is pitching, he is setting himself up to be a very important member of the Mets’ pitching staff heading into the Postseason.