PHILADELPHIA -- The Orioles wanted no part of Bryce Harper in the 10th inning on Tuesday night at Citizens Bank Park.

So they did something that surprisingly few teams have tried this season. They intentionally walked him, even though it meant putting the game-winning run on first base with two outs. Harper is having an MVP-caliber season. In fact, he might be the favorite to win his second National League MVP Award. But it was only the 11th time this season he has been intentionally walked. J.T. Realmuto made Baltimore pay for it. He ripped a 2-1 changeup into the right-field corner to score automatic runner Ronald Torreyes from third and Harper from first in a 3-2 walk-off victory.

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It kept the Phillies’ postseason hopes alive with 11 games to play.

The Phils (77-74) sit three behind the Braves (79-70) in the NL East, after Atlanta beat Arizona on Tuesday at Chase Field. If the Braves finish 6-7, they will have an 85-win season. In that scenario, the Phillies will need to finish 8-3 to tie.

It shows how catastrophic a loss on Tuesday would have been.

“We need all of them,” Realmuto said. “This late in the season, where we’re at, a few games behind the Braves, we can’t afford to lose two or three in a row anymore.”

Harper went 2-for-4 with one walk and two strikeouts. But he also committed two baserunning gaffes that could have been costly. He got thrown out in the third trying to turn a hard-hit single to right into a double. Harper was on third with one out in the eighth. He broke for home on Matt Vierling’s chopper to second baseman Pat Valaika, but he did not leave on contact. In fact, he initially took a step back toward third before he ran home.

Harper was out by several feet.

“It ended up being a bad [read], getting thrown out at the plate right there,” he said. “It can’t happen.”

Harper denied that he was trying to make something happen for an offense that had struggled to score against Baltimore. The Orioles entered the game with a 5.91 ERA, which is the highest ERA by any team since the 1999 Rockies (6.01 ERA) and the third-highest ERA by any team since 1940. The Phillies scored only one run in their first 18 innings against the Orioles, then they hit in the 10th trailing by a run.

Odúbel Herrera grounded out to advance Torreyes to third. Jean Segura struck out swinging for the second out.

Harper prayed he might get an opportunity to hit. Fat chance.

“I always ask Joe [Girardi] and [hitting coach] Joe Dillon, ‘What do you guys think? Are they going to pitch to me?’” Harper said. “And they always tell me no. I think Girardi said to me last time: 'If it's me there's no chance.'"

"I didn’t want Harper to beat us there,” Orioles manager Brandon Hyde confirmed. “Realmuto is an All-Star, superstar-type player. I didn’t want him to beat us either. We just made pitches too close to the plate there with their pinch-hitter on deck.”

The Phillies had Andrew Knapp standing in the on-deck circle. He is batting .158 in 146 plate appearances. Realmuto said he thought they might try to pitch around him to get to Knapp, but he prepared anyway. He had never faced César Valdez before, so he got a quick scouting report on his changeup from Segura and from Freddy Galvis, who played with the Orioles earlier this season.

Valdez threw Realmuto a first-pitch changeup for a strike, making him think that he might get a pitch to hit. The second and third pitches were nowhere near the zone. But the fourth pitch was just off the plate.

Realmuto connected.

“You can’t sit here and be super passive in that situation after they threw you a strike,” he said.

Realmuto said he thought Orioles right fielder Anthony Santander had no chance to catch the ball, but the longer the ball hung in the air, it looked like he might have a chance. It dropped.

“It was a pretty stressful 90 feet there,” Realmuto said.

Harper bolted for second base and never stopped running. He planned to atone for his earlier mistakes.

“There’s no chance I wasn’t going to try to score,” Harper said. “I thought I got a good read, a good jump. Then I heard the crowd roar once it landed. I kicked it into another gear.”