BALTIMORE -- Coming off their best surge of the season, the Red Sox arrived at Camden Yards on Monday with the news that key starter David Price had landed on the injured list with left elbow tendinitis. 

The corresponding roster move -- selecting the contract of righty Ryan Weber from Triple-A Pawtucket -- was an afterthought when the day started. 

But by the time a 4-1 loss to the Orioles had ended, Weber had done something that could be vital when it comes time for the Sox to try to regain their momentum on Tuesday night. 

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Weber saved the bullpen with a lights-out performance that you didn’t necessarily see coming, considering the 28-year-old has spent the bulk of his professional career (as in 239 out of 265 appearances over 11 seasons) in the Minor Leagues. 

You also might not have seen it coming because Weber had a 5.04 ERA in his five starts for Pawtucket this season. 

But baseball can be full of surprises, and this was a pleasant one for the Red Sox. 

“I mean, I felt really good, everything was working,” said Weber. “Threw strikes, got ahead of everyone. And when I needed the strikeout, I was striking guys out. Slider was working. But staying in there and giving the team a chance was big.” 

Over four scoreless innings, Weber gave up three hits, walked none and struck out four. 

“He’s a guy that … it’s not like the radar gun is lighting up your eye, but movement will be there,” said Red Sox manager Alex Cora. “He does a good job changing speeds. He had his changeup, the breaking ball, two-seam fastball, front-door [pitches] to get lefties out, he worked the ball in and out of the zone. He pitched.” 

With Hector Velázquez starting in place of Price on Tuesday in what will likely amount to an “opener” situation, it was big for Weber to do what he did. 

“I knew that’s why I was coming up,” said Weber. “I knew there were two so-called bullpen days and I just wanted to keep the pitch count low. Even if I gave up runs, I wanted to keep the pitch count low and just stay out there so I could save the bullpen and maybe sneak a win tomorrow out of the bullpen day.” 

Starter Josh Smith went 3 2/3 innings on Monday and gave up four runs, all on a grand slam by Jonathan Villar. Heath Hembree got the final two outs in the fourth, and Weber went the rest of the way.

It was a long but enjoyable day for Weber, who caught a 7:15 a.m. flight to Baltimore but felt rejuvenated when it was time to pitch.

“Got in around 9:30 to the hotel, rested up and got it cranking up,” Weber said.

Of Weber’s 55 pitches, he threw 21 sinkers, 19 changeups and 15 cutters. Of the 11 balls the Orioles put in play against Weber, the average exit velocity was just 83.5 mph.

The way the Red Sox had been hitting of late (30 runs over their final three games against the White Sox over the weekend), they expected the collective performance by the pitching staff would be enough to win in this one.

But Orioles lefty John Means and two Baltimore relievers stifled the Sox, holding them to just three hits on the night.

“It’s going to happen [sometimes],” said Cora. “Obviously we don’t like it. You’ve got to give credit sometimes to the opposition. They pitched well today.”

Despite the defeat, the Sox have won six of their last eight. They are six games behind the first-place Rays in the AL East.