BOSTON -- With a mighty blow off the bat of Tyler O'Neill, the Red Sox were able to escape Wednesday night’s tilt against the Orioles with a 5-3 victory in 10 innings at Fenway Park.

With the win, Boston was able to take two in the three-game set with Baltimore in a battle of playoff contenders.

The Sox (74-72) remained four games behind the Twins (78-68) and one back of the Tigers (75-71) for the third and final American League Wild Card spot, with 16 games to play. Both Minnesota and Detroit won on Wednesday.

“It’s getting harder and harder, but it’s realistic,” manager Alex Cora said of the postseason race. “We just won a series against one of the best teams in the big leagues. Obviously, in our situation, it’s not enough. We’ve got to continue.”

Now, Boston gets set to kick off a crucial four-game series against the AL East-rival Yankees in the Bronx starting on Thursday night.

“That was a big series for us right there,” said O’Neill. “Baltimore has been a really good team all year, top of the division, top of the league, they have a lot of talent. It was good to come out with a series win today. Nick [Pivetta] did a really good job at shutting them down all game.”

Trailing, 3-2, in the bottom of the 10th, Jarren Duran, the automatic runner, moved to third on a one-out error, which put Wilyer Abreu on and set the stage for O’Neill. The Statcast-projected 393-foot home run over the Green Monster was O’Neill’s second walk-off winner this season.

“It’s huge,” Cora said. “We’ve been pitching, which is awesome. Hopefully, at one point we start hitting again. Just grind out the game and we took advantage of one mistake, and T.O. put a good swing on it.

“We obviously needed this one. Hopefully, it’s the beginning of something big.”

Pivetta took a no-decision despite his quality outing. He departed with a 2-1 advantage after working six strong innings, allowing just four hits and one walk, while working out of tight jams with some massive strikeouts.

It was the second straight start in which Pivetta allowed just one run in six innings of work, but he did not earn a decision for the third time in his last four outings.

“With Nick, if you look at the last few years here, in September, he always finishes strong,” Cora said. “He loves to compete, that’s the cool thing about him. He’ll be ready for the next one.”

“I was able to execute the pitches,” said Pivetta, who relied heavily on his fastball and breaking ball. “So, it gave me a lot more room to continue to go through with that game plan. I was staying ahead of the count, throwing strikes. I was able to do what I needed to do.”

Pivetta retired nine batters via K’s, including two in a row in the second with a runner on third and one to close out the fifth with an Oriole on third.

“The stuff keeps getting better throughout the year,” Cora said of his starter. “He makes adjustments throughout, he’s very thoughtful of it, he knows his mechanics and he knows how to use his stuff.”

Pivetta yielded a solo home run to Emmanuel Rivera in the third inning, which gave Baltimore a 1-0 lead.

Boston would strike right back in the bottom half of the third to tie the game and in the fourth, the Sox took a 2-1 lead when Ceddanne Rafaela brought Masataka Yoshida in with an RBI single.

Baltimore evened the score in the top of the eighth on Anthony Santander’s 41st home run and Rivera gave the O’s a 3-2 lead with an RBI single in the top of the 10th. It was the 19th time since the All-Star break the Red Sox surrendered a lead in the sixth inning or later, but they were saved by O’Neill’s 30th home run of the season, which gave Boston its sixth walk-off win of the year.

“Late in the game, extra innings, you want to come up clutch for the team,” O’Neill said. “I’m just trying to get the runner from third, first and foremost, and I put a good swing on that one for sure.”