It’s one thing to give up runs. It’s another thing to show signs of a tired arm in the MLB Playoffs.

Oct 13, 2024; Los Angeles, California, USA; Los Angeles Dodgers pitcher Jack Flaherty (0) throws a pitch against the New York Mets in the fifth inning during game one of the NLCS for the 2024 MLB Playoffs at Dodger Stadium. Mandatory Credit: Kiyoshi Mio-Imagn Images Oct 13, 2024; Los Angeles, California, USA; Los Angeles Dodgers pitcher Jack Flaherty (0) throws a pitch against the New York Mets in the fifth inning during game one of the NLCS for the 2024 MLB Playoffs at Dodger Stadium. Mandatory Credit: Kiyoshi Mio-Imagn Images / Kiyoshi Mio-Imagn Images

The Los Angeles Dodgers had to feel confident in their chances to advance to the World Series on Friday in Game 5 of the NLCS. On the mound, they had Jack Flaherty, who was magnificent in Game 1. However, the Flaherty of Game 1 certainly didn’t show up in Game 5.

It would be one thing if Flaherty just had a rough first inning. It happens. He gave up four runs in his first postseason start in the NLDS. But this wasn’t just one of those days. The pitcher showed worrying signs of arm fatigue that could impact the Dodgers if they make it through.

Flaherty gave up three runs in the first inning on a massive blast from Pete Alonso. He allowed three hits and walked another two.

Codify Baseball laid out the concerning numbers: Flaherty has averaged 93.3 mph on his fastball this season. In the first inning, only two fastballs even made it up to 93. His Game 1 fastballs were in the range of 94-92 mph. A two mph drop to 90-92 is a bad sign.

Jack Flaherty’s velocity was worryingly down in Game 5

Flaherty is on four days rest. He got seven days rest between his last two postseason starts. Throughout the regular season, he was given five days of rest between starts. The last time he went on four was in July.

It could just be a case of arm fatigue. It could also be some underlying issue dogging Flaherty. That would be the worst-case scenario but it also seems the most unlikely. The Dodgers likely would have had a much shorter leash with Flaherty if something was ailing him.

Even if it is fatigue, that’s a problem unto itself. Los Angeles may need Flaherty to be ready to go on four days rest in the World Series. If he can’t be relied upon unless he’s fully rested, that’s an issue.

Flaherty’s troubles in Game 5 were especially frustrating because he went seven innings in Game 1, giving up just two hits and holding the Mets scoreless.