SAN DIEGO -- The Cardinals on Friday night ended a streak of 19 scoreless innings. That, however, doesn’t mean the team’s offense has corrected course.

If anything, the offense accelerated in the wrong direction by losing its top power threat in a 3-1 loss to the Padres in the opener of a weekend series at Petco Park.

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Left fielder Marcell Ozuna, who leads the Cards with 20 home runs and 62 RBIs, was placed on the injured list after he exited in the middle of the third inning with a right hand injury sustained on a pickoff at first base. The Cardinals announced on Saturday that Ozuna had small fractures at the base of the third and fourth fingers on his right hand.

“Clearly, it's significant enough for him to go on the IL,” manager Mike Shildt said Friday night.

Along with Ozuna's placement on the IL, right-hander John Brebbia was put on the paternity list and outfielders Lane Thomas and Tyler O'Neill were recalled from Triple-A Memphis.

The absence of Ozuna is a huge blow to a Cardinals team that has lost four straight games and has had to scratch for runs of late. In the past nine games, the Cardinals have gone 3-6 and have averaged 2.8 runs per game.

“It’s a dent, for sure,” Shildt said. “This is a guy who’s had an All-Star-caliber first half in all facets of the game -- excellent defense, runs the bases really well and, clearly, he’s hit 20 homers. We’ve got to find a way to replace him.”

Ozuna was injured on the final play of the top of the third. With Jose Martinez at the plate and the count full, Padres left-hander Eric Lauer threw to first. Ozuna dived toward the bag hands-first and was called safe. Ozuna pulled his right hand back from the bag, however, seemingly wincing in pain while first baseman Eric Hosmer kept the tag on. After a replay review, Ozuna was called out.

By then, he had already walked off the field while looking at his right hand. He came out of the game and was replaced in the bottom of the inning by Yairo Munoz.

“I have concerns,” said Ozuna, who also tops Cardinals batters with an .847 OPS. “We’ll see how it is tomorrow.”

Ozuna will be out of the lineup until after the All-Star break. The Cardinals are at 40-40 one game before the halfway point of their season. They will need to cover for Ozuna quickly or risk losing touch in the National League Central before his return.

“We’re just trying to figure out a way to score runs,” Shildt said. “We’re doing what we can to put ourselves into the best position we can on the bases. But, ultimately, we’ve got to drive people in."

The Cardinals’ only RBI on Friday belonged to their pitcher, Michael Wacha. He ended the 19-inning scoreless streak with an infield single in the fourth inning. That was the Cardinals’ first run since the second inning Tuesday vs. the A’s, and it didn’t come easy -- it required a replay review.

Wacha’s grounder up the middle with runners on second and third was stopped on a diving play by shortstop Fernando Tatis Jr., and first base umpire Vic Carapazza called Wacha out at first. That call was overturned after the Cardinals challenged.

It appeared for a while that Wacha might make the one run hold up. He took a shutout into the sixth inning but then surrendered back-to-back solo home runs by Tatis and Hosmer. Wacha lasted seven innings, allowing two runs, six hits and a walk.

As the offense is searching for a turnaround, Wacha has found his. He has three quality starts in his four outings since he returned to the rotation June 10 and has lowered his ERA a full run to 5.30.

“I’m executing pitches a lot better now, throwing it where I want it to be,” he said.