SAN FRANCISCO -- Steven Duggar saved the Giants a couple of runs with a fantastic diving catch Wednesday afternoon, but it likely came at a cost.

Duggar was forced to depart the Giants’ 4-1 loss to the Nationals at Oracle Park after injuring his surgically repaired left shoulder in the fourth inning. The 25-year-old defensive whiz raced into the right-center-field gap to snag Juan Soto’s bases-loaded liner and end the inning, but he came down hard on his shoulder, causing him to grimace visibly.

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Austin Slater came in to replace Duggar in right field the following inning. Manager Bruce Bochy said Duggar sprained his left shoulder on the play, and he will undergo an MRI to assess the severity of the injury.

“I feel terrible for the kid,” Bochy said. “He got over the last time he hurt it and was playing pretty good baseball. A little setback, but we’ll have more info here soon.”

It was more bad news for the Giants, who have now lost nine of their past 13 games and suffered their first sweep since May 24-26 against Arizona. The recent slide has dimmed their once-fledgling postseason hopes, causing them to fall four games out of the National League Wild Card race. Six teams remain ahead of them in the standings, including the Phillies, who come to town Thursday for the start of a pivotal four-game series at Oracle Park. Philadelphia holds the second NL Wild Card spot, sitting one game ahead of St. Louis.

Duggar’s injury comes at an inopportune time for the Giants, who are already down an outfielder after losing slugger Alex Dickerson to a right oblique strain.

Duggar required surgery to repair a torn labrum in his left shoulder last September after suffering the injury on a dive back to second base. He was not permitted to dive for balls during Spring Training as he worked his way back, but the Giants lifted the restriction at the start of the regular season. Duggar has experienced a few close calls with his shoulder this year, but none were as concerning as Wednesday’s.

With Duggar seemingly heading to the injured list, the Giants will likely add another outfielder from Triple-A Sacramento such as Chris Shaw or Jaylin Davis, who was acquired from the Twins as part of the Sam Dyson trade last Wednesday. Shaw is a more likely candidate, as he is already on the 40-man roster. He is batting .300 with a .958 OPS and 15 home runs over 52 games with Sacramento after opening the season at Double-A Richmond.

The Giants could use another power-hitting bat to help boost their sagging offense, which produced only four runs in three games against the Nationals. They’ve averaged only 2.8 runs per game over their past 13 games, batting just .178 with runners in scoring position since July 24. Brandon Belt (10-for-57 since July 21), Brandon Crawford (6-for-37 since July 27) and Mike Yastrzemski (2-for-17 since Saturday) are among the hitters who have tumbled into recent slumps. Crawford drove in San Francisco's lone run in the ninth inning on Wednesday.

“You’re going to miss a guy that’s swinging the bat well like Dickerson,” Bochy said. “That’s going to affect your club, no getting around that. But everybody has to deal with injuries. You just hope we pick it up somewhere else. Right now, we’re just not clicking. These things are hard to explain.”

Anderson departs with blister

Rookie Shaun Anderson was pulled after throwing 66 pitches over three innings Thursday due to a blister on the middle finger of his right hand. He departed after allowing four runs on four hits and three walks in the shortest outing of his young career.

“We were trying to take care of it this past week,” said Anderson, who has logged a 5.33 ERA over 16 starts with the Giants. “I was feeling good in that first inning, and then it eventually broke open. It’s something I had to deal with. I wanted to keep going, but the trainers thought, for my best interest, it was better to come out.”

Anderson was scheduled to make his next start for the Giants on Tuesday against the A’s, but Bochy said he could miss his next turn to give the blister more time to heal. With an off-day on Monday, the Giants could skip Anderson’s spot and temporarily go with a four-man rotation.

Anderson gave up a run in the first inning, but his biggest mistake came in the third after he misplaced a fastball that former Giants outfielder Gerardo Parra drove out to left-center field for a three-run homer that gave the Nationals a 4-0 lead.

“The first inning, I felt great, a lot better than I had felt in my recent outings,” Anderson said. “I was kind of fired up for that. It’s unfortunate how things played out, but I’m going to get this right.”