Stay or Go: Should Mets re-sign Taijuan Walker?

When the Mets signed Taijuan Walker in late-February of 2021, right around the time spring training started, it was viewed as a shrewd and important move that brought a potentially high-upside starter to a team that was in dire need of a starting rotation reinforcement.

And during his two-year career with the Mets, Walker has been pretty reliable and pretty good. 

In those two seasons, Walker has a 3.98 ERA (4.11 FIP) and 1.18 WHIP in 316.1 innings over 58 starts and one relief appearance.

Walker was even a well-deserved first-time All-Star in 2021 and could've easily been chosen for the team again for his performance in the first half of 2022.

Along the way, Walker has been much more dependable than he was early in his career with the Seattle Mariners, but has dealt with second-half regressions each season with the Mets.

With Jacob deGrom signing with the Texas Rangers, Chris Bassitt a free agent after declining his $19 million option, and the Mets picking up Carlos Carrasco's $14 million team option, Walker's future in Flushing is cloudy.

Walker opted out of his $6 million option and the Mets declined to make a qualifying offer to him so he's officially a free agent. 

According to SNY's Andy Martino, the Mets are looking to bring in a mid-rotation starter and Walker is on a list of names they are considering.

But should the Mets bring Walker back?

WHY IT COULD MAKE SENSE TO LET WALKER GO

The most concerning thing about Walker's Mets tenure has been how he has fallen off after the All-Star break each year.

In 2021, Walker had a woeful 7.13 ERA (6.79 FIP) in 64.1 innings over 13 starts from July 18 to the end of the season, allowing a whopping 20 home runs along the way. However, it's fair to believe part of those struggles were due to the enormous innings increase Walker shouldered that season, jumping from 53.1 in 2020 (after barely pitching in 2018 and 2019 due to injury) to 159 in 2021.

But Walker faded again in the second half of 2022.

In 65.2 innings over 13 starts from July 26 to Oct. 4, Walker had a 4.80 ERA (4.59 FIP) while allowing 11 home runs in those 13 starts after giving up just four over his first 16 starts of the season.

Another concern when it comes to Walker is how emotional he can be on the mound at times when things don't go his way, which has allowed some innings to spiral on him. The most notable came on July 18, 2021 when Walker knocked a fair ball foul and proceeded to have a meltdown against the Pirates in Pittsburgh. 

Additionally, Walker was a liability in two late-season starts against the Braves this season, lasting just one inning on Aug. 5 (when he allowed eight runs) and leaving his Aug. 16 start after two innings due to back spasms. 

Walker's advanced stats were also quite ugly in 2022, though that comes with the caveat that he has often outperformed his advanced numbers -- including having an ERA that has been lower than his FIP in every season since 2016.

But while Walker's advanced stats don't tell the full story, one would imagine that at some point -- and especially with Walker not missing many bats -- this is going to catch up with him. 

A look at Walker's advanced stats from 2022 show that he was well below average when it came to hard hit percentage, average exit velocity, whiff percentage, and strikeout rate, and below average when it came to xERA/xwOBA, xBA, xSLG, and barrel percentage. And most of those numbers were worse than the ones he put up in 2021. 

WHY IT COULD MAKE SENSE TO KEEP WALKER

Despite his shortcomings, Walker has been a reliable performer for the Mets over the last two seasons.

As Walker exceeded 157 innings in both 2021 and 2022, deGrom threw 156.1 innings combined, Carrasco was limited to 53.2 innings in 2021 before throwing 152 in 2022, and Tylor Megill -- who looked like a budding star early in 2022 -- was limited to just 47.1 innings due to injury. Even Max Scherzer missed significant time, and wound up tossing just 145.1 innings in 2022. 

With the exception of Bassitt, who tossed a career-high 181.2 innings this season, Walker was the Mets' most reliable starting pitcher in terms of availability. 

So while Walker has regressed in the second half the last two seasons (and his 2021 regression was much more alarming than the one he had in 2022), he has taken the ball with regularity.

Walker has also had dominant stretches at times, including a 13-start run from this past May 12 to July 16 when he had a 2.23 ERA (2.65 FIP) in 80.2 innings while allowing between zero and two earned runs in nine of those starts.

As far as Walker's stuff, his fastball velocity has remained very consistent. It spiked at a career-high 94.2 mph average in 2021, but has otherwise averaged between 93.2 mph and 93.9 mph every season since 2016 -- it was 93.5 mph in 2022. So there shouldn't be a concern that he's about to drop off a cliff. 

Walker also added a split-finger fastball in 2020 that has become a key part of his arsenal (he used it 27.3 percent of the time in 2022) and should help keep hitters off-balance going forward. 

VERDICT

With so much uncertainty in the Mets' rotation, the decision on Walker is a complicated one.

On one hand, he often takes the ball and pitches -- and can go on runs of dominance. But his second-half regressions and advanced numbers are big concerns, and the Mets should be seeking pitchers who have plus stuff and tons of upside or pitchers who can be relied on to be mostly consistent.

Even though Walker has been a solid and successful Met overall, now feels like the time to move on.