Brandon Marsh out of the lineup with the Phillies facing a second straight lefty starter vs. Dodgers

Phillies interim manager Don Mattingly has been thinking about giving Brandon Marsh a break against left-handed starters.

Marsh, who was out of Wednesday’s starting lineup against Dodgers lefty Eric Lauer, had a .262 batting average against left-handed pitchers across the first three months of the season. The strides he made helped him become an everyday player for the first time in his career.

But lately, amid his first extended slump of the season, there’s been regression. In 20 plate appearances against lefties in July, Marsh has been held to a .105 average.

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Marsh had a well-hit fly ball against Justin Wrobleski on Tuesday that was caught on the warning track, which was Mattingly’s justification for not pinch-hitting for him in the ninth inning against Dodgers left-handed closer Tanner Scott. Marsh wound up hitting a 47.5 mph ground ball, and two ensuing baserunning miscues led to a game-ending double-play.

“I’ve been planning, when we see the lefties coming back-to-back like this, we’ve always been trying to give him a day in that,” Mattingly said. “It is something that I’m thinking about and looking at, because obviously the numbers haven’t been great against the lefties. I liked some of his at-bats early, but that seems to have been a battle as we’ve gone on.”

The addition of right-handed hitting Bryan De La Cruz to the roster has given Mattingly some more flexibility. De La Cruz, an outfielder, started in right field on Wednesday. Edmundo Sosa started in left and Derek Hill started in center.

De La Cruz was activated Tuesday after Garrett Stubbs landed on the injured list with left wrist inflammation. Mattingly said the injury was something Stubbs had been “dealing with” for a while.

“I just think another right-hand bat in the outfield, it frees Sosa up a little bit for the infield, because we can go all right out there if we want,” Mattingly said. “ … It kind of gives you the second at-bat if we get to the mode where we pinch-hit, and then you get back to the next guy, and they go left-handed on a lefty. That gives you an extra guy. So that’s the thought right now.”

Mattingly managed De La Cruz previously in Miami.

“He could play all three, probably better in right or left, but comfortable at all three spots in the outfield,” Mattingly said. “So it gives us another guy out there.”

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The Phillies will not skip the fifth spot in their starting rotation during their upcoming series against the Yankees, Mattingly announced. They will instead keep everyone in order.

The Phillies have lost the last 10 games started by the fifth spot of the rotation, a streak that includes Andrew Painter’s last five appearances before he was optioned in June. With an off day on Thursday, the team could bypass the No. 5 turn entirely by having the rest of the rotation pitch on regular rest.

But Mattingly said his bigger concern is the starters’ long-term health.

“Giving them that, take advantage of the off days when we can,” Mattingly said. “We’ll have stretches where they’re on every fifth. But try to take advantage. I mean, it’s kind of the backbone of our club, and it’s not one of those things you want to take chances with. Anything can happen, but I think we, as much as we can, we want to try to keep those guys, give them the extra day.”

Mattingly declined to announce yet who will take the ball when the No. 5 spot comes up on Saturday against the Yankees. Since he was optioned on June 20, Alan Rangel is ineligible to be recalled until Aug. 4, unless an injury occurs on the major league club.

Painter made his fourth appearance for triple-A Lehigh Valley on Tuesday. In five innings, he allowed two earned runs on seven hits and one walk. Painter struck out eight. … Following Thursday’s off day, Jesús Luzardo (9-4, 3.43 ERA) will start the series opener Friday against Yankees right-hander Will Warren (7-4, 4.03).