David Peterson's latest struggles could be an issue for the Mets

After being the Mets' most dependable starter for most of the season, David Peterson has hit a rough patch at the wrong time.

Aug 19, 2025; Washington, District of Columbia, USA; New York Mets starting pitcher David Peterson (23) reacts after the third out against the Washington Nationals during the first inning at Nationals Park. Mandatory Credit: Amber Searls-Imagn Images | Amber Searls-Imagn Images

While the New York Mets have had rotation issues this season, the one constant has been dependability from lefty David Peterson. 2025 has been a breakout season for Peterson, who made his first All-Star Team this year and has been the team's most reliable starter in terms of length, especially in a stretch from mid-June through mid-August where he was the only pitcher going six innings in a start.

The final line for David Peterson, who allows a career-high eight runs against the Marlins pic.twitter.com/HkztsImLAf

— SNY Mets (@SNY_Mets) August 30, 2025

But the Mets got a rare stinker from Peterson on Saturday, when he allowed a career-high eight earned runs in 2+ innings pitched. While bad defense played a factor in extending the early innings for Peterson, his command was off from the jump and is part of a bad trend for Peterson over the past month or so.

David Peterson’s last 5 starts:

7.56 ERA, 21 earned runs, 28 hits, 15 walks in 25 IP.

— Just Mets (@just_mets) August 30, 2025

Peterson has struggled mightily since the start of August, going 1-1 with a 7.56 ERA in six starts, a run that includes one brilliant outing in Washington where he allowed one run in eight innings of work. MLB.com's Anthony DiComo notes that the returns for Peterson have been diminishing for a while, pointing out that Peterson's ERA is close to 5 over his past 13 starts.

David Peterson just didn't have it today. He allowed eight earned runs to the Marlins, the highest total of his career.

Peterson's first 13 starts: 2.49 ERA
Peterson's last 13 starts: 4.96 ERA

— Anthony DiComo (@AnthonyDiComo) August 30, 2025

This kind of performance is a problem for the Mets, who likely have Peterson penciled in to start Game 1 of their first postseason series, whether it is in the Wild Card round or the National League Division Series. There may be a relatively simple explanation for Peterson's struggles of late, and it comes down to a classic pitching problem.

David Peterson Has Already Hit A Career High In Innings Pitched

While most fans associate innings concerns with younger pitchers breaking into the bigs, Peterson has not really had a true starter's workload throughout his career. Making his debut in the 2020 pandemic-shortened season meant the 29-year-old only established a baseline of 49.2 innings pitched, and he had not exceeded 21 starts in a season prior to this year.

Read More: Mets' emerging ace receives bold prediction for postseason

This season has seen Peterson throw 152 innings over his first 26 starts, setting career highs in both departments. It is easy to forget that Peterson missed the first two months of the 2024 campaign after undergoing offseason hip surgery, allowing him to rack up a combined 133.1 innings between the regular season and playoffs, being used as a reliever during the latter.

Most pitchers will have some issues with fatigue if they either set career highs in innings pitched or reach innings totals they haven't achieved in a while, which the Mets experienced last year as both Luis Severino and Sean Manaea began to wear down by the time the postseason rolled around. While the Mets didn't have the ability to ease their workloads down the stretch as they were fighting just to get in the dance, the team's stronger postseason positioning this time could help Peterson out.

Manager Carlos Mendoza indicated recently that the Mets are going turn-by-turn through their rotation, sticking with a six-man alignment to get through their current stretch of 16 games in a row without a day off. The Mets do play 10 days in a row again after that off day, but they have more rotation depth to allow them to either continue with a six-man group or skip a starter to give them a more extended rest period.

Rosters officially expand on Monday, allowing the Mets to add another bullpen arm if they opt to bypass a starter their next time through the rotation. Tylor Megill is also close to returning from his rehab assignment with Triple-A Syracuse while prospect Brandon Sproat has been pitching well for a while down there, giving the Mets a lot of starting options to give Peterson (or any other tiring pitcher) a breather if they need it.

The Mets' postseason odds sit at a shade over 96%, and a critical four-game series in Philadelphia next week will make it clear whether the Mets have a realistic shot at catching the Phillies in the National League East. If the division odds are unrealistic at that point, don't be shocked if the Mets skip a start for Peterson or piggyback him with another pitcher to give him a bit more rest to be more effective in October.