BALTIMORE -- The day Christian Arroyo came back from his injury was the same day the Red Sox revealed that Trevor Story’s right hand injury had gone from a bone bruise to a hairline fracture.

That date was July 30, and it felt like a big blow in a series of medical maladies this season for Boston.

But something funny happened that day. Arroyo belted three hits -- and he hasn’t stopped hitting since.

Stepping in again for the injured Story at second base on Saturday, Arroyo had three more hits, including a pivotal, insurance RBI double in the ninth that was the difference in a 4-3 victory over the Orioles at Camden Yards.

There’s still no word on when Story, who last played for the Red Sox on July 12, will be back. Arroyo has lessened the urgency with the hottest offensive run of his career.

“Oh, it’s huge,” said Michael Wacha, who fired 5 2/3 scoreless innings to earn Saturday’s win. “Ever since he’s come back, he’s a hit machine. Hustling around, playing really good defense and coming through in some big-time spots and driving in runs. That’s been huge for us.”

It was on July 9 that Arroyo went on the injured list with a left groin strain. At the time, he was hitting .224 with a .640 OPS in 116 at-bats.

How much have things changed since his return? Arroyo is batting .397 (29-for-73) over those three weeks. That includes six doubles, a triple, a homer and nine RBIs, not to mention a .977 OPS.

“I think I've made some adjustments, looking back at some videos, some things timing-wise that have helped me out a little bit, simplifying things,” said Arroyo. “I think sometimes you get a misconception where you might want to try to do too much. You want to swing hard and you want to go for exit velos or whatever the case is. You want to hit for power. I think that stuff just kind of comes naturally, so for me it’s just about getting a ball in the strike zone, being in position to hit and hitting it hard.”

Arroyo’s nine hits in his last four games are his career-high for a four-game stretch.

Not only that, but Arroyo has started 19 of the 20 games since he’s been back, which is big for a former first-round Draft pick who has had durability issues throughout his career.

“Like, right now, I’ve been calling him Cal Ripken,” quipped Red Sox manager Alex Cora. “Like, ‘Let’s keep going, kid.’ I’ll check on him always, like, ‘How do you feel?’ Of course he’s going to say ‘I’m ready.’ But the medical staff and the support staff, they’ve been amazing with him and he’s done an amazing job.”

Once he was back, Arroyo was determined to be able to post every day for Cora. 

“When I was coming back this time, it was obviously a little different with Trevor down, so it was important to put myself in a position to feel good every day,” Arroyo said. “There’s little things. After the game, consistently getting in the cold tub, getting stretched out, coming in early, making sure I get on top of it instead of just letting things build up. I’ve got a good routine going on, and hats off to everyone behind the scenes. I can’t do this stuff alone.”

Before the Red Sox signed Story in March to be their starting second baseman, Arroyo was atop the depth chart at that position.

It was an alignment the club was comfortable with, having watched Arroyo perform well at times when getting regular playing time last season, including the postseason.

“Like I always said, he was a high pick and talented, very talented. He can hit the ball out of the ballpark. He hits for average. He’s a good defender and all that,” said Cora. “The problem has been the injuries. To be honest with you, when he’s the only guy playing [a position] like that, when he’s the main guy, we can play him a lot. When he’s run into trouble is when he’s the utility guy and he doesn't’ play for a few days, that’s when he has issues.”

There are no issues for Arroyo these days. He keeps playing and he keeps hitting.