Did Orion Kerkering just change the Phillies’ postseason plans?

I’m not saying that you should pencil the Phillies’ Orion Kerkering into the eighth or ninth inning of Game 7 of the National League Championship Series.

I’m also not saying that you should rule it out.

Fact is, you can’t. Not after watching what the 22-year-old righty did to a trio of Mets hitters in his major league debut on Sunday night.

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It took Kerkering just 12 pitches to retire Omar Narvaez, Brett Baty and Rafael Ortega in the bottom of the eighth inning. Granted, these weren’t exactly the ‘27 Yankees. Years from now, baseball’s literary canon is unlikely to include any wistful memoirs centered on the summer of the ‘23 Mets. All three of the batters Kerkering faced had an OPS below .650. Baty and Narvaez have been two of the worst hitters in the game this season, given their workload. The Phillies bullpen is going to need to navigate a gantlet this postseason, and it ain’t constructed out of Rafael Ortega.

That being said …

This was a situation in less-than-ideal weather with the Phillies needing a win to trim their magic number to one. In setting down the Mets in order, Kerkering did something that Gregory Soto had failed to do in the eighth inning in each of the previous two nights. In holding a lead, he did something that Craig Kimbrel failed to do his last time out on the mound. Most impressive was the way that he did it.

Kerkering’s slider is a pitch unlike any that you will see at any level. He uses it more like a cutter than a slider. The 10 that he threw on Sunday had three times as much horizontal break as a league-average slider, per Statcast. To give you some idea, this season, Zack Wheeler’s slider has averaged 2.5 inches of horizontal movement. On Sunday, Kerkering’s averaged 16.5.

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The result is a pitch that is even more devastating against lefties than it is against righties. In the minors this season, Kerkering struck out 38 of the 92 lefties he faced, allowing just one home run and holding them to a .125/.163/.182 line. That’s remarkable.

Righties fared better, but still weren’t great: .229/.294/.358 with 43 strikeouts and three home runs in 119 plate appearances.

In his debut on Sunday, all three of the batters Kerkering faced were lefties. Narvaez topped a grounder to third, while Baty and Ortega struck out.

So, what now?

Kerkering clearly has a weapon that can play in the postseason. The two big questions: 1) Does he have enough time to earn Rob Thomson’s trust? 2) How much of a workload can he handle?

“The only thing with guys coming up here is how they’re going to handle this environment,” Thomson said after the Phillies’ 5-2 win over the Mets. “How they’re going to handle the third deck, 40,000 people, the passion of the city. And he looked like he wasn’t even sweating out there.”

Thomson is clearly ready to find out the answers. The Phillies called up Kerkering in part due to necessity. Kimbrel logged a rare back-to-back-to-back last week and needed at least another day of rest. José Alvarado had pitched three times in four days. Soto had pitched in back-to-back games and three times and four days.

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That said, you have to think that this was partially a fact-finding mission. The Phillies have a ton of options for their postseason roster, and an equal number of question marks.

Right now, the Phillies probably have nine locks for their 13 pitching spots on the postseason roster: Wheeler, Aaron Nola, Ranger Suárez, Kimbrel, Alvarado, Seranthony Domínguez, Matt Strahm, Soto, and Jeff Hoffman.

That leaves four open spots for a list of candidates that will include current active roster members Taijuan Walker, Cristopher Sánchez, Michael Lorenzen, and Dylan Covey, plus potentially 40-man roster members Andrew Bellatti, Yunior Marte, and Luis Ortiz.

Plus Kerkering.

Judging by what we saw Sunday night, Kerkering clearly warrants being one of the four. In fact, the four seem pretty obvious: Walker, Sanchez, Lorenzen, Kerkering. Really, the only question is Lorenzen, who had a big bounce-back appearance on Sunday, pitching a scoreless ninth inning for the save. In his previous eight outings, he’d allowed 30 runs in 26⅓ innings. But there really isn’t anybody who would warrant forsaking the guy we saw in his first two starts after the trade deadline.

Now, let’s go back to that second question about Kerkering. What kind of role can he handle?

A recurring high-leverage role seems like a long shot. He’s just a year-and-a-half removed from being drafted in the fifth round out of South Florida. The Phillies were careful with his usage this season. He has never pitched on back-to-back days. In fact, he has had only one stretch in which he made two straight appearances with less than two days of rest.

One scenario is that the Phillies keep him on the roster as a specialist of sorts. As we saw last postseason, there are plenty of situations that call for a strikeout arm other than one of the usual back-of-the-bullpen guys. You can picture plenty of scenarios in which Kerkering’s slider is the Phillies’ best chance.

A lot could depend on these final six games. The Phillies could get him three more outings by pitching him every other day through the end of the regular season on Sunday. One thing we know for sure: It will be fun to watch.