BOSTON -- When manager Mark Kotsay announced on May 25 that the A’s would be utilizing the opener role, he envisioned the decision would help build the confidence of some of the team’s younger starters.

One such starter is Luis Medina, who made his Major League debut on April 26 against the Angels. Since then, Medina has compiled a 6.34 ERA over eight starts and four appearances following an opener.

Medina’s first half of the season was a mixed bag, much like his most recent line in Oakland’s 7-3 loss to Boston on Friday night at Fenway Park. Following opener Sam Long, Medina went six innings for the third time this season, giving up four runs on seven hits with one walk and a career-high nine strikeouts.

In his four outings as the bulk-innings guy behind an opener, Medina has a 5.23 ERA, compared to his 6.92 mark across eight starts.

“For us it’s about building confidence, putting them in the best situations for success,” Kotsay said. “Obviously, tonight was a little bit more of a tough spot for him to come in, that wasn’t ideal. But ultimately it’s landing them in an easier spot.”

Long, who made his first start since July 8, 2022, went one inning before turning the ball over to Medina with the bases loaded and none out in the second. Medina came on and promptly struck out Connor Wong on five pitches. The 24-year-old then allowed all three of Long’s runners to score on two singles and a wild pitch.

After giving up another RBI single, Medina retired his next 13 batters.

“It was a good start,” Medina said through team interpreter Ramón Hernández, “it was a bad start at the beginning. And I got a couple ground balls, but they were [hit] where nobody was, so nothing you can do with that.

“But besides that, I think my stuff was good. I was competing, I was doing my best out there, trying to help the team win.”

Medina, who typically favors his four-seamer, utilized a five-pitch mix (fastball, slider, sinker, curveball and changeup). Five of his nine strikeouts came on the slider, a pitch Medina has been working on.

“I thought he had a great mix,” Kotsay said. “The slider was a wipeout slider tonight and the fastball played up. So he was beating guys with his heater and really, really throwing the slider in the zone and it was a swing-and-miss pitch.

“He’s worked on that and I think that’s only going to make him better going forward.”

“The plan was: attack the strike zone, so it makes the breaking balls look better,” Medina said. “Help out with the breaking ball when you attack the zone with fastballs, and that was the plan today.

“Attack the strike zone, throw a lot of fastballs early and try to make them chase the slider.”

After pitching four clean innings, Medina ran into trouble in the seventh.

With two outs and Jarren Duran on third after hitting a leadoff triple, Medina intentionally walked Rafael Devers before a mound meeting with catcher Shea Langeliers to discuss their plan of attack against cleanup hitter Adam Duvall.

Considering Duvall had seen a lot of breaking balls in his previous three at-bats, Medina and Langeliers thought it was a good opportunity to throw him a two-seamer on the inside of the plate.

Duvall connected on the pitch and hit a grounder to shortstop Tyler Wade. An extra step by Wade resulted in a close play at first where Duvall managed to beat the throw, allowing Duran to score.

“I thought he did a great job, even there in the seventh, you know, with Tyler making that play for him,” Kotsay said. “He walks out of there with no runs and even a better line. So, overall the kid did a great job.”

Regardless of when he enters the game, Medina has impressed his teammates and is already showing growth in his young career.

“Obviously he’s got really good stuff,” Langeliers said. “He’s come a long way. He’s learning, he’s growing. We’re in constant communication, just about how he feels, what feels good, just kind of learning together how to sequence pitches and where his stuff performs best in the strike zone and stuff like that.

“I think the sky’s the limit for him.”