Brett Anderson’s return a horrendous one for Dodgers

This was not what Brett Anderson envisioned during those seemingly endless weeks of core-strengthening and stretching exercises, of weightlifting and long toss, of coping with the tedium of rehabilitating from major surgery.

The Dodgers left-hander spent five months working his way back from a bulging disk in his lower back, only to have his long-awaited return last all of one horrendous inning in Sunday’s 11-3 loss to the Pittsburgh Pirates.

Anderson gave up five runs and five hits, two of them home runs, in a 30-pitch inning in which the Pirates batted around and tossed the Dodgers into a hole far too deep from which to climb out.

Adding injury to insult, Anderson suffered a mild left-wrist sprain when he fell on his hand while diving in an attempt to stop Adam Frazier’s dribbler after the first-inning damage had been done.

The oft-injured Anderson, who has made eight trips to the disabled list in eight years and had elbow ligament-replacement surgery in 2011, got pitcher Chad Kuhl to line out to end the inning but was removed to start the second. He was listed as day to day and is hopeful of making his next start, but by no means is he a lock.

“It feels like I’m kind of snakebit … it’s like a nightmare you hopefully wake up from,” Anderson said, his left wrist in a brace. “You never expect to dive and hurt your wrist, especially with all the time you put in to get back to a big league mound.

“And then to have it happen in the first inning, you just kind of say, ‘What the heck do I have to do? Be the boy in the bubble or something?’ It’s crappy, but the small silver lining was that I got out there, not for very long, but hopefully I’ll come in [Monday], feel better and pitch better next time.”

The most positive development for the Dodgers on Sunday occurred 400 miles up the coast, where San Francisco blew a six-run, seventh-inning lead and lost to Baltimore, 8-7. That allowed the Dodgers to remain one game behind the Giants in the National League West.

At Dodger Stadium, Josh Harrison smacked Anderson’s first pitch, a 92-mph fastball, to center field for a single. Jordy Mercer capped an eight-pitch at-bat with a two-run homer to left.

Anderson retired Andrew McCutchen (fly to center) and David Freese (grounder to shortstop) but walked Jung Ho Kang and gave up a single to Francisco Cervelli. Sean Rodriguez then lined a 2-and-0 fastball into the right-field seats for a three-run homer and a 5-0 lead.

“His sinker was elevated, and he was working behind in the count,” Manager Dave Roberts said. “Brett, as I’ve seen in the past, works with a good tempo and gets ground balls. Getting behind and leaving fastballs up is not his game.”

Anderson’s wrist stiffened after the inning, and he was replaced by Brock Stewart, marking the sixth time in 13 games that a Dodgers starter has gone four innings or less.

Stewart, called up from triple-A on Sunday morning, gave up one run in three innings, and Grant Dayton fired two scoreless innings to highlight an eight-inning bullpen effort, which came on the heels of Saturday’s 7 1/3-inning relief effort in the wake of Brandon McCarthy’s injury-shortened start.

“To put our bullpen in that situation is just embarrassing on my part,” Anderson said. “I want to be a guy who gets penciled in to stabilize the rotation. Obviously, that didn’t work out today. But hopefully, fingers crossed, [the injury] won’t be too major, and I can start doing that my next time out.”

X-rays on Anderson’s wrist were negative, but his status will depend on how he responds to treatment.

“There are no broken bones or tears,” said Anderson, the 29th pitcher and 13th starter the Dodgers have used this season. “Hopefully, I can flush out the inflammation and get back out there when they ask me to.”

mike.digiovanna@latimes.com

Twitter: @MikeDiGiovanna