Insider pinpoints 1 prospect Mets should promote to solve bullpen struggles

This top New York Mets prospect could make a major impact in the team's bullpen.

May 15, 2024; Philadelphia, Pennsylvania, USA; New York Mets logo on the sleeve of J.D. Martinez during a game against the Philadelphia Phillies at Citizens Bank Park. Mandatory Credit: Bill Streicher-Imagn Images | Bill Streicher-Imagn Images

The New York Mets' bullpen holds a respectable 3.77 collective ERA throughout the 2025 MLB Season, which puts them at 10th overall in the league.

However, this stat doesn't tell the entire story, especially because the Mets' relief corps was the best in all of baseball for about the first two months of this season. This highlights just how much they have struggled since that point.

Read more: NY radio host shreds Juan Soto amid Mets losing woes

Not to mention that Edwin Diaz has been one of baseball's best closers, and his success has kept the Mets' collective ERA down. Without Diaz being so consistent, the bullpen's overall performance would be a much different story.

Jul 15, 2025; Cumberland, Georgia, USA; National League pitcher Edwin Diaz (39) of the New York Mets pitches in the ninth inning during the 2025 MLB All Star Game at Truist Park. Mandatory Credit: Brett Davis-Imagn Images | Brett Davis-Imagn Images

MLB Insider Thinks Mets Should Promote Top Pitching Prospect

The good news for the Mets is that they have several elite pitching prospects whom the organization could decide to use as the season reaches its postseason stretch. And in an August 7 article, New York Post MLB insider Jon Heyman shared a strong stance on which prospect New York should promote to improve their bullpen.

Heyman suggested the Mets should promote Nolan McLean, who is their No. 3 overall prospect and No. 2 pitcher, according to MLB.com. He noted that while other pitching prospects like Jonah Tong and Brandon Sproat also deserve consideration in getting called up to the big leagues, he seems to suggest that McLean's stuff is the most MLB-ready to this point.

Or at least he thinks that McLean's stuff will play the best out of the bullpen, especially in a one-inning role or later in games.

https://t.co/yunL6qYQS9. MLB Insider: Two suggestions each for free-falling Yankees and Mets

— Jon Heyman (@JonHeyman) August 8, 2025

Who is Nolan McLean?

Anybody who has been following the Mets' prospects in recent years is surely well aware of Nolan McLean, who the franchise drafted out of Oklahoma State in the third round (No. 91 overall) in the 2023 MLB Draft.

McLean has produced an impressive 3.11 ERA and 238 strikeouts in 222.2 innings pitched in his minor league career to this point, which includes the past three seasons.

In 2025, however, he boasts a 2.46 ERA between Double-A and Triple-A (along with 120 strikeouts in 109.2 innings pitched), which suggests McLean is continuing to improve.

Nolan McLean lowers his Triple-A ERA to 2.81!

5.2 IP | 1 H | 0 R | 3 BB | 7 K

MLB's No. 10 right-handed pitching prospect (@Mets) posts his sixth scoreless outing of the season for the @SyracuseMets: pic.twitter.com/yc1cJHFVUO

— MLB Pipeline (@MLBPipeline) August 6, 2025

It will be fascinating to see whether the Mets elect to promote McLean over the next month or so, and in what role they will use him if they indeed decide to bring him up to the show.

Regardless, Mets fans can expect to see McLean playing in Citi Field soon enough.