"He's answered the physical question, for sure," Boston manager John Farrell said.
Buchholz (12-1) allowed up three runs and seven hits in seven innings, and Daniel Nava and David Ortiz hit three-run homers for the Red Sox, who had an 8-0 lead by the third inning. Dustin Pedroia added three hits, and Jarrod Saltalamacchia had a three-run drive overturned in a video review.
The win left the AL East champions needing one more win or a loss by Oakland to clinch the AL's best record. The Athletics won 8-2 at Seattle on Friday.
Given a big lead before his first pitch, Buchholz rebounded from a loss to Toronto last weekend. A strained neck that cost him three months interrupted what has been a stellar season statistically. His ERA is 1.74, and he's 6-0 with a 1.40 ERA in seven road starts. He's also 4-0 with a 1.74 ERA in his last four starts against Baltimore.
"It's a good stepping stone," Buchholz said. "I'm just glad the team could score all those runs. There wasn't a whole lot of stress in the outing today."
That was probably for the best, given that Buchholz's routine was upset by the team's off day Thursday, when he said he basically slept all day.
"My body felt a little lethargic tonight," he said. "I felt when I woke up this morning that it might be a grinding outing for me today, which I felt I needed, too. Anybody can go out there when you have your best stuff."
Adam Jones' two-run homer in the third was the first home run by a right-handed hitter off Buchholz this year. Buchholz also gave up Chris Davis' major league-leading 53rd homer in the sixth.
Scott Feldman (5-6) allowed eight runs and eight hits in 2 1-3 innings for the Orioles, who have lost seven of nine.
"It would've been nice to finish up a little stronger heading to the offseason coming off a good game," Feldman said. "But the bottom line is, we all, everybody in here, wanted to make the playoffs and we didn't do it. Hopefully next year we'll get in there."
Boston hit for the cycle as a team in the first, when Mike Napoli had an RBI double, Nava sent a first-pitch curveball in the right-field bleachers, and Stephen Drew hit an RBI triple.
Saltalamacchia's drive off Feldman in the third hit the top side of the cushion atop the right-field wall and caromed back onto the field. After the play Initially ruled a home run, umpires reviewed the video and gave Saltalamacchia a double that left two men on. Drew followed with a two-run single off Zach Britton.
Ortiz hit his 30th homer in the eighth, the first batter faced by former Boston College pitcher Mike Belfiore in his major league debut.
"Welcome to the big leagues," Ortiz said. "I heard he's from Boston, too."
Ortiz tied Ted Williams' team record for 30-homer, 100-RBI seasons with seven. ... Davis' homer was his 28th at home, breaking the previous franchise record set by Frank Robinson in Memorial Stadium in 1966. Davis was back in the lineup after missing one game with a sore right foot. An X-ray on Thursday showed nothing worrisome. "It was more about just letting me catch my breath," Davis said. ... Jones' homer was his career-best 33rd, one more than last year. ... Red Sox OF Shane Victorino sat out with a nagging thumb injury. "Fully expect he'll be in the lineup tomorrow," Farrell said. ... Napoli went 1 for 3 with two walks in his return to Boston's lineup after missing four games with a left foot injury, and CF Jacoby Ellsbury was 0 for 4 in his second game after missing 16 with a broken right foot. ... A handful of Red Sox players debuted a new slogan before the game, wearing red T-shirts that read: "3 lines, 2 Chainz, 1 goal."
Copyright by STATS LLC and The Associated Press
BALTIMORE, MD - SEPTEMBER 27: David Ortiz #34 of the Boston Red Sox celebrates with manager John Farrell #53...
30,774 (66.9% full) - % is based on regular season capacity
70 degrees, partly cloudy
Home Plate - Adrian Johnson, First Base - Bill Welke, Second Base - Brian O'Nora, Third Base - Fieldin Culbreth
Papi's 30th homer of the season puts him in further rarefied air. Ortiz joins Ted Williams as the only players in Sox history with seven seasons of 30 homers and 100 RBI, breaking a tie with former teammate Manny Ramirez.