This story was excerpted from Anthony DiComo’s Mets Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

MLB.com's Joe Trezza filled in on this edition of the Mets Beat newsletter.

When the Mets last faced Sean Manaea as a starting pitcher on April 20 this past season, they didn’t have much trouble, using a five-run fourth inning to hand the veteran lefty and the Giants a 9-4 defeat. When New York saw Manaea again later in the year, as a reliever, the results flipped. Then, it was the Mets who had trouble with Manaea, who logged a combined four innings of one-run ball on consecutive days (June 30-July 1) against New York.

On their surface, results like these shouldn't mean much due to the small sample size. But the differences in these outings can be instructive now for the Mets, who agreed to a two-year deal with Manaea this weekend to supplement the back of their rotation. Why? Because Manaea was undergoing something of an evolution around that time, as he navigated a demotion to the bullpen following an ineffective early stretch of the season.

The version of Manaea the Mets faced in April didn’t much resemble the Manaea that found success with the A’s from 2016-21, or even the one that struggled with San Diego in 2022. And he didn’t resemble the pitcher who finished strong this past September. Manaea had abandoned his sinker for a four-seam fastball and was throwing harder, but with uncharacteristically poor command. He was relying disproportionately on his slider, and it wasn’t working -- thanks in part to the Mets, Manaea lugged a 7.96 ERA into mid-May.

Now they are betting the Manaea that pitches for them in 2024 doesn’t resemble that Manaea, and with good reason.

That’s because Manaea became a different pitcher as the year wore on, revamping his pitch mix with a brand-new pitch -- a sweeper -- that helped turn his season around. With the help of that pitch, he turned in a respectable 3.78 ERA and an impressive 3.26 FIP over his final 81 innings of the season.

The sweeper was integral to that turnaround -- hitters slashed just .140/.161/.163 against the pitch as it racked up a 35.1% whiff percentage. By June, it became the second-most used pitch in Manaea’s arsenal, as he began using it in favor of his slider and changeup, particularly against left-handed batters.

Check out Manaea's monthly numbers from 2023:

Sweeper usage
• May: 4 percent
• June: 18.7 percent
• July: 17.4 percent
• August: 25 percent

ERA
• May: 3.93
• June: 5.17
• July: 4.91
• August: 3.15

And take note of Manaea's season splits:

First 11 appearances
• 32 2/3 innings
• 6.61 ERA
• 28.9% strikeout rate
• 12.5% walk rate
• 32.6% ground ball rate
• 8 homers

Final 26 appearances
• 85 innings
• 3.60 ERA
• 24.2% strikeout rate
• 6.6% walk rate
• 44% ground ball rate
• 6 homers

Manaea then put the sweeper back aside when he returned to the rotation for four September starts and he pitched well enough in those outings (2.25 ERA) to feel comfortable opting out of his contract to test the open market. The Mets, buying into the adjustments, rewarded him with a deal that's worth $28 million and includes an opt-out after the 2024 season, according to a source. They clearly think the changes Manaea made last year are real, and that they signal good things to come.