LOS ANGELES -- The Phillies are shorthanded again, and at the worst possible time.

They not only watched Mookie Betts hit a go-ahead home run in the seventh inning and a two-out single to score an insurance run in the eighth in Tuesday night’s 5-3 loss to the Dodgers at Dodger Stadium, they lost two of their best players in the middle of a difficult six-game road trip.

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Bryce Harper left the game with tightness in his lower back in the fourth inning.

Jean Segura left the game with a left groin injury in the ninth.

“It's tough,” Phillies manager Joe Girardi said. “We need some guys to step up tomorrow. I'm not sure exactly what this means. But we're going to need some guys to step up tomorrow.”

Harper tweaked his back taking a swing in the fourth inning. It seemed clear that something was wrong because he stepped out of the box and took a long time to return to finish the at-bat. He struck out swinging and the Phillies immediately removed him from the game.

“He didn’t look right to me,” Girardi said.

It is a growing concern. Harper suffered back soreness the final month of last season. He said in February in Clearwater, Fla., that an MRI exam in the offseason revealed an issue with the QL (quadratus lumborum) muscle.

To help his back this winter, Harper started to hit a month later than normal (pushing it back from Jan. 1 to Feb. 1). The Phillies brought him along slowly at the beginning of camp. He then missed a game in April because of lower back tightness. Both Girardi and Harper said then they think it is something he can manage throughout the season.

Girardi said that sentiment has not changed.

“It is the feeling that I get,” he said. “I mean, I think he'll be a player for us on Friday. I can't tell you about tomorrow.”

Segura, however, sounds like he could miss some time. He pulled up after hustling to reach on an error in the ninth. He was replaced by a pinch-runner and immediately walked off the field and went into the clubhouse.

“I’m not so confident that’s day to day,” Girardi said.

The Phillies have been without shortstop Didi Gregorius since last month. Now they might play Wednesday’s series finale against the Dodgers and beyond without Harper and Segura, too. It makes the remaining four games of this road trip through Los Angeles and San Francisco more daunting.

It certainly made Tuesday more challenging. Luke Williams moved from shortstop to take Harper’s place in right field. Ronald Torreyes entered the game at shortstop and took Harper’s spot in the lineup.

That spot came up in a big situation in the fifth. The Phillies scored twice and had a runner on second with two outs when the Dodgers intentionally walked J.T. Realmuto to face Torreyes, who popped out to Dodgers first baseman Albert Pujols to end the inning.

Travis Jankowski pinch-hit for Torreyes in the eighth. He walked and stole second base. Rhys Hoskins walked to put runners on first and second with no outs. The Phillies did not score. They were 1-for-9 with runners in scoring position.

“Guys have to step up,” Hoskins said. “The rest of the lineup, right? That’s what we did the last couple of weeks. That’s what we’ll have to do now, and if it happens again, that’s what we’ll have to do. Guys will have to step up and keep this thing afloat while guys get healthy.”

Hoskins might have been a candidate to get Wednesday off to clear his mind. He is in an 0-for-33 skid. Ryan Howard (2015), Raul Ibanez (2011) and Joe Morgan (1983) each had 0-for-35 skids for the Phillies. Desi Relaford (1998), Len Matuszek (1982-83) and Danny Murtaugh (1942-43) hold the Phillies' franchise record (non-pitcher) for longest hitless streak at 0-for-36.

But without Harper and Segura, Hoskins almost certainly will have to play.

“I’m either swinging and missing or fouling back,” Hoskins said. “You can’t do that in this league. The guys on the mound get paid to get guys out, too. If you get behind, they make pitches and throw the pitches they want to. It’s a tough league to hit in. Yeah, sometimes you miss pitches and you get in these little funks and that’s how it goes, but there’s always the end. And I always feel like when I come to the ballpark every day that the end of this is near or it’s here. That’s where I’m at.”