Buchholz will try to build on that with another stellar start against the Astros and keep them winless at Fenway Park on Friday night.
Buchholz (5-7, 5.99 ERA) is 1-2 with a 7.50 ERA in five starts since tossing a three-hitter with a career-high 12 strikeouts in an 11-0 rout in Houston on July 13. He had allowed seven runs in five innings in back-to-back starts before giving up three in eight innings and striking out eight Saturday against the Los Angeles Angels.
Buchholz nearly took the loss until Boston scored a run in the eighth in a 5-4 loss in 19 innings.
"I thought tonight was probably his best outing of the year. He was outstanding. He had a good curveball when he was in fastball counts and slowed some hitters down," manager John Farrell told MLB's official website. "He had three distinct pitches tonight and looked like the Clay Buchholz we know."
The Red Sox (55-65) have won four in a row since that loss and scored seven runs in the sixth inning in a 9-4 victory Thursday against Houston. Dustin Pedroia capped the sixth with a two-run double and finished with three hits in the opener to an 11-game homestand.
"We came to life. We were able to combine some base on balls with some base hits," Farrell said.
Boston improved to 16-4 all-time versus the Astros (50-72) and 8-0 at Fenway. Houston matched a season high with its sixth consecutive road loss.
The Red Sox will try to add to those marks when they face Dallas Keuchel (10-8, 3.07), who had a run of strong outings snapped Sunday. The left-hander tied a season high by giving up five runs over six innings in a 6-2 loss to Texas.
Keuchel, 1-1 with a 0.78 ERA in his prior three starts, didn't allow a hit in his first three innings.
"You can't be on your game all the time, but I thought the first three innings was about as good as I've been this season," he told MLB's official website. "It's very frustrating. We'll come back and be better."
Keuchel is making his first start versus Boston, and recently acquired Yoenis Cespedes has the most experience against him among Red Sox hitters. Cespedes, who returned to the lineup Thursday after leaving Wednesday's 5-4 win in Cincinnati with a bruised right hand, is 5 for 10 with a double against Keuchel.
Pedroia, batting .368 in his last 19 games, is hitting .478 (33 for 69) in a 17-game hit streak against Houston.
The Astros' Chris Carter, hitting .354 with seven homers and 18 RBIs in his past 12 games, is batting .188 in his last nine against the Red Sox but is 2 for 6 lifetime versus Buchholz.