Brandon Marsh injures hamstring, Taijuan Walker struggles in Phillies’ 10-inning loss to Cardinals

Rob Thomson knew right away.

In the eighth inning Sunday night, with the Phillies pushing for the go-ahead run, Brandon Marsh slammed on the brakes after rounding second on a single by Nick Castellanos. He grimaced, then hobbled back to the base before Thomson and a trainer arrived to check on him.

Marsh exited with what the Phillies characterized as a right hamstring strain, the extent of which was not yet determined after a 5-4, 10-inning loss to the Cardinals. Marsh was still undergoing treatment. Thomson said the team will know more Monday.

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There isn’t much use in speculating on whether Marsh will miss time, though doing so might help change the subject from the 41-19 Phillies’ only reasonable roster debate: Should Taijuan Walker remain in the rotation as the No. 5 starter?

(More on that shortly.)

If Marsh is sidelined, Cristian Pache would figure to get more playing time in left field. Kody Clemens, scratched from the series finale against the Cardinals due to back spasms, could be a lefty-hitting platoon option. Ditto for David Dahl, who has major-league experience — and 12 homers in triple A, four in the past week.

Or maybe Marsh will be able to play in a day or two, while Rhys Hoskins’ Brewers — it still sounds weird, doesn’t it? — are in town this week.

But Thomson could tell as soon as he ran out to second base that Marsh would have to leave the game.

“I just saw it in his face. He was in pain,” Thomson said. “We’ll find out more [Monday]. They’ll look at it and see. He’s day to day — at this point.”

Through one-third of the season, the Phillies have avoided significant injuries, save the strained left hamstring that has sidelined Trea Turner since May 3. But annoying issues are cropping up. Fill-in shortstop Edmundo Sosa was available to play only in an emergency after tweaking his right hamstring Saturday night. Clemens was unavailable. Now Marsh.

It helped explain why Thomson stuck with Pache, who struggles against right-handed pitching, in the 10th inning against Cardinals closer Ryan Helsley. Pache struck out before Castellanos struck out with the tying run on third base to end the game.

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Try as they might, the Phillies were unable to take Walker entirely off the hook. And they did try.

In front of another jam-packed crowd — 41,190 paying customers — and a national television audience, they tied the game on a rally started by, of all things, back-to-back bunts by Garrett Stubbs and Johan Rojas that went a total of 31 feet. Stubbs’ shimmy after an RBI double and José Alvarado’s scream at the Cardinals’ dugout after holding them scoreless amid a home-run challenge in the ninth inning were amusing distractions.

But Gregory Soto gave up a two-out single by Nolan Gorman, which scored the automatic runner from third base in the 10th inning. And the focus shifted again to Walker, who put the Phillies in early 2-0 and 4-2 holes.

“It’s just frustrating,” Walker said. “Obviously the team’s playing so well right now, and I just want to be a part of that and help the team. But I’m just not doing my part right now.”

Making his seventh start since missing the season’s first month with an injured shoulder, Walker allowed two-run homers to Gorman in the first inning and Alec Burleson in the third. He struggled with his command, gave up a lot of hard contact, and threw 93 pitches in five innings.

Walker’s up-to-the-minute ERA: 5.73.

“He left the ball up a couple times,” Thomson said. “The two home runs were just cutters that were left out over the plate. I’ve seen his command better.”

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Everyone can agree that Walker is the weak link in the National League’s best rotation. But he’s also a No. 5 starter. All any team, even a World Series contender, asks of its fifth starter is to log innings each time his turn comes around, then take a seat during the playoffs.

Unlike most teams, though, the Phillies have another option. Spencer Turnbull had a 1.67 ERA in a half-dozen starts while Walker was sidelined and could step back in. But Turnbull might be needed to fill in for Ranger Suárez, who escaped serious injury after taking a line drive off the left hand Saturday night but could need extra time before his next start.

Suárez and Walker are lined up to start Saturday and Sunday in London. Most likely, the Phillies will kick the can down the road with Walker for another few starts, even though he isn’t doing much to strengthen his case.

“He’s got to keep the ball down, and he knows that,” Thomson said. “We’ll just keep working on it.”

Walker’s best pitch is his splitter. It has been hit more often than usual lately, so he mixed in sinkers, sweepers, and even curveballs against the Cardinals before realizing that the splitter was more effective and leaned on it more in the fourth and fifth innings.

Gorman tucked a cutter around the right-field foul pole for his homer. Burleson hit a full-count sweeper out to right. Walker gave up a double to Iván Herrera and a single to Michael Siani on splitters.

Asked what he needs to do to not give up as much hard contact, Walker didn’t hesitate.

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“Stay out of the middle of the plate,” he said. “I’m leaving too much stuff over the middle. Two balls today, two pitches, just left over and the guy hit it hard, turns into a two-run home run.

“I thought the splitter was the best that it’s been all year. It was really good. Now that I’ve got that part, I can start throwing that a lot more and mix it in a lot more going forward. It’s just frustrating.”

And it will remain a talking point unless Walker gets it figured out.