2 NY Mets players whose late collapse is a red flag moving forward, 2 whose isn't

Kodai Senga’s late-season collapse should set off warning signals

2025 was Kodia Senga’s first semi-healthy season after missing most of 2024 due to shoulder problems. Heading into August, Senga looked like he could win Comeback Player of the Year. Throughout his first 85 innings, Senga had a 2.00 ERA, 3.75 FIP, and 1.21 WHIP. He was striking out batters at an above-average 23.4% rate, but had a mediocre 11.7% walk rate. But he excelled at limiting home runs and hard contact, with a 0.74 HR/9, 88.2 MPH exit velocity, and 7% barrel rate. 

But Senga would only pitch 27.2 more innings after the end of July. In that time, he allowed 19 earned runs, only struck out 20.6% of opponents with a sub-par 10.7% walk rate, and was giving up far more home runs and hard contact. This time, Senga was nailed for a 1.63 HR/9, 90.3 MPH exit velocity, and 10.2% barrel rate. Things got so bad for Senga that the Mets sent him to Triple-A at the start of September to figure things out.

The red flags for Senga’s second-half collapse started at the beginning of the year. Senga’s four-seam fastball velocity came in at 94.7 MPH, both prior to his mid-June injury and after it. His fastball also lost movement, and it resulted in a much less effective pitch. In 2023, opponents had a .244 BA, .399 SLG%, and .338 wOBA vs his fastball. This year, they batted .279 with a .543 SLG% and .391 wOBA. Even Senga’s signature ghost-fork was less effective. A .210 xwOBA and 41.8% whiff rate are both still elite, but a step back from the .182 xwOBA and 59.5% whiff rate he had on the same pitch in 2023. His Stuff+ came in at just 95 for the season, a significant drop from 101 in his 2023 rookie campaign. His 2.00 ERA and 3.75 FIP weren’t as good as they looked, either. He had a 4.47 SIERA and 4.28 xFIP. During August, he had a 4.65 SIERA and 4.59 xFIP. It also seemed Senga fooled fewer batters. His out-of-zone swing rate in April-July was 29.4%, but fell to 26.7% in August.

Senga will be another year removed from shoulder issues in 2026, but it will be his age-33 season. Hopefully for his sake and the Mets’ sake, this was his way of fully recovering after nearly missing an entire season. However, given his age and decline in overall performance, one has to question if his August was only a sign of things to come.