BALTIMORE—On September 28, 2011, in the final game of the season, the Orioles ended the playoff hopes of the Boston Red Sox with a walk-off single by Robert Andino. Ten years later, with the Red Sox entering Tuesday night’s game with a one-game lead for the second American League wild-card berth, the Orioles pulled off an unlikely win, beating Boston and Chris Sale, 4-2, before an announced crowd of 8,098 at Camden Yards.

It was the Orioles’ first win after six straight losses to Boston (88-69). Sale (5-1) had won 10 straight decisions over the Orioles (51-106). The Orioles’ starting pitcher was Bruce Zimmermann, whose last start was on June 13th. He set the tone for a dominant performance by Oriole pitching by allowing just one run in four innings.

While the Red Sox were losing, the New York Yankees were beating the Toronto Blue Jays after sweeping the Red Sox this past weekend. The Yankees have a two-game lead in the wild-card race. The Red Sox lead the Seattle Mariners by a half-game and the Blue Jays by a game.

“I want to stay competitive,” manager Brandon Hyde said. “We’re facing good teams that put themselves in a good position to play in October. Hopefully, someday we’re going to be in that spot. Until then I just want to stay competitive, try to give everybody a good game and give us a chance to win every single night. Fortunately, our pitching and our defense did that tonight.”

The Orioles scored three runs against Sale in the bottom of the sixth. Two perfect innings by Joey Krehbiel, who has thrown 4 1/3 hitless innings since joining the Orioles last Friday, enabled them to hold the lead.

“Didn’t know much about him a few days ago,” Hyde said. “Twelve pitches in two innings … I loved the aggressiveness, the way he comes in and pounds the strike zone.”

Cole Sulser pitched a spotless ninth for his eighth save. Leftfielder Ryan McKenna made an excellent running and leaping catch on J.D. Martinez’s drive to end the games. Marcos Diplán, Krehbiel and Sulser combined to retire the last 12 Boston batters.

Sale allowed just a second-inning single by Pedro Severino in the first five innings.

Kelvin Gutiérrez led off the sixth with a base hit. With one out, Ryan Mountcastle drilled a 414-foot home run to left to tie the score, 2-2. It was his 32^nd homer.

“It was a great team win,” Mountcastle said. “We pitched really well. We had big hits throughout the game and overall played great defense, too. Definitely a good win for us.”

Austin Hays singled after Mountcastle’s home run, and Hansel Robles replaced Sale. Trey Mancini and Severino followed with singles, and Hays scored to give the Orioles a 3-2 lead.

“Our middle of the order did a really good job of taking some at-bats and using the whole field,” Hyde said. “We did some really good things offensively against one of the elite starters in this game.”

Zimmermann was coming off the 60-day injured list and allowed only two hits, but one was Kyle Schwarber’s 32^nd home run in the second. The Ellicott City native, who missed time because of left bicep tendinitis and a sprained right ankle, knew it wasn’t going to be a long assignment.

“I can’t ask for much more than that,” Zimmermann said. “I knew I was only going to [go] four or five innings. I just wanted to go out there and have a strong outing and keep the game in play for the rest of the guys coming in behind me.”

Zimmermann could close the Orioles’ season on Sunday in Toronto.

Diplán (2-0) took over for Zimmermann in the fifth, and he gave up Hunter Renfroe’s 29^th home run in the sixth.

The Orioles took a 4-2 lead with three consecutive two-out singles by Mancini, Severino and McKenna in the eighth against Tanner Houck.

There are two more home games against the Red Sox, and three final games in Toronto.

“You get to play spoiler, which is a lot of fun,” Zimmermann said. “As a Baltimore native, growing up, this is the anniversary of Andino, the Red Sox killer. I was a kid watching that game. It’s definitely a lot of fun to be able to do that on the anniversary of that game.” 

Notes: Zac Lowther (1-2, 7.66 ERA) will face Nathan Eovaldi (10-9, 3.88) on Wednesday. … Severino had three hits, equaling his season high.