The Padres have cooled off from a red-hot June, and after Jonny Gomes' pinch-hit walk-off home run gave the Red Sox a 2-1 victory on Wednesday, San Diego has lost five games in a row.
The losing streak ties a season high for the Padres, but both prior skids came during a tough 5-15 start in April.
The Padres are 1-5 on their current 10-game road trip and will try to avoid being swept in the series finale in Boston before taking on the Nationals.
It will be no easy task against the Red Sox, who have won seven of eight and own the best record in the American League and the best home record in the Majors.
San Diego will send left-hander Eric Stults, who's arguably been the club's ace so far this season, to the mound. He is looking to bounce back from one of his worst starts in what has otherwise been a strong season. The Marlins tagged him for seven hits and six runs (five earned) in 3 2/3 innings on Saturday.
"I just didn't feel like I could command my pitches tonight like I had been feeling," Stults said. "I had a pretty good stretch of starts here where I felt really good just with my delivery. Something was a little bit off."
Over his last 11 starts, Stults is 4-4 with a 2.80 ERA while holding opponents to a .229 average. He has 44 strikeouts in that span.
Red Sox starter Allan Webster is looking for his first career win on Thursday in his fifth career start. He showed improvement in his last start, surrendering four earned runs on six hits in six innings on Friday, but did not factor into the decision against the Blue Jays.
Boston's No. 4 prospect is 0-2 with a 9.50 ERA while filling in for the injured Clay Buchholz.
"It felt really good the first four innings. I was locating my fastball, being able to get quick outs and stay in there," Webster said after the game against the Jays.
Padres: Cabrera nears comeback
The Padres expect to reinstate shortstop Everth Cabrera from the disabled list by Friday if his left hamstring feels good after running the bases and playing defense during his rehab assignment.
After playing on Tuesday and Wednesday for Class A Fort Wayne, Cabrera could actually rejoin the team on Thursday, although he isn't likely to be activated.
"Cabbie looked comfortable and was able to handle a few plays at shortstop and see a lot of pitches," said Padres vice president and assistant general manager A.J. Hinch, who saw Cabrera play. "He looked excited to be back on the field."
• Will Venable hopes to return to the lineup on Thursday after missing the last two games with a sore left hamstring,
The outfielder said he thinks the injury happened while running the bases on Saturday against the Marlins. Venable played on Sunday but left the game in the eighth inning, and the team wanted to give the hamstring some extra rest.
"It was weird, because the triple the second day in Miami, I was coming around second and I stumbled a little awkwardly," he said. "Because Miami is so humid, I didn't feel anything [immediately]. Then in the middle of the night, it felt tight."
Red Sox: Buchholz throws from longer distance
Buchholz played catch at 100 feet on Wednesday as he moves closer to returning from a neck strain that landed him on the disabled list. He hasn't pitched since June 8.
"It's finally turned a corner actually," said Buchholz. "I feel like I'm finally getting close to feeling pretty much normal now. So the last few days of throwing are encouraging. Like I said, I'm finally able to clear my head a little bit and go about it as just getting back to getting off the mound."
The next milestone is 120 feet before the Red Sox permit him to throw off a mound, and then the team will set a plan for a rehab assignment.
• Red Sox manager John Farrell had a positive update on injured catcher David Ross, who has been out of the lineup since June 14 with his second concussion of the season.
"He's had three or four really good days consecutively here," said Farrell. "He's still got next Tuesday as a follow up with Dr. Collins in Pittsburgh. His scheduled return for us is undecided right now. But he's started to work out with some exercise on elliptical, stationary bike. He's started to throw a little bit.
"He's started to lift some weights. The sensations that he feels as a result of the concussion are starting to really diminish. Most importantly, when he gets into open-space areas where you've got a lot of movement and a lot of noise, that's starting to really subside."
• Wednesday was the eighth walk-off win of the season for the Red Sox, tying the Giants for most in the Majors.
• The Padres trail the all-time series 9-5, including a 3-5 mark in Boston.
Jamal Collier is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.