Asked a few hours before his first big league Opening Day how he -- his eligibility retained during a dazzling debut last season -- felt about entering 2021 as a Rookie of the Year Award candidate, Ryan Mountcastle was mostly diplomatic. He “won’t press to win awards,” Mountcastle said, stressing he needs only to “go out there and play my game.”

The rest, it was implied, would take care of itself.

Only then did he go off-script a bit, letting a sprinkle of his confidence show through.

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“And if I do that,” Mountcastle said. “I think I have a pretty good shot of getting it.”

That’s certainty possible if Mountcastle continues to contribute the way he did Friday, when he paired with John Means to lead the Orioles to their 3-0 season-opening win over the Red Sox at Fenway Park.

Cranking a go-ahead two-run double off the Green Monster in the sixth, Mountcastle complemented seven sterling innings from Means on the mound to cement a clinical victory on a cold day in Boston.

Making his first career Opening Day start, Means carved through the Red Sox lineup to outduel Nathan Eovaldi. He permitted just two baserunners while throwing 97 pitches, the lone hit allowed going to his first batter, Enrique Hernández. After Xander Bogaerts reached on an error to begin the second, Means sent down 18 consecutive hitters to finish his day, striking out five and walking none. For the 2019 All-Star, it was, objectively, the finest start of his career.

“That was the best I’ve seen him pitch,” manager Brandon Hyde said. “I thought he did an amazing job. It was just a clinic, pitching wise.”

It was also one of the finer Opening Day starts in Orioles history. Means became the first O’s pitcher (since at least 1901) to go seven-or more innings on Opening Day allowing one hit or fewer. He also became just the third pitcher in baseball history to do so without also issuing a walk, joining Irv Young in 1906 and Jordan Zimmermann in 2019. Means has now allowed one run or fewer in five straight starts dating back to last season, tied for the second-longest streak in O’s history (Jim Palmer owns the record, with six starts in 1978).

“It was pretty special,” said Means, who made his MLB debut at Fenway in 2018. “It was amazing to have my family there. Fenway Park holds a special place in my heart. It was a really cool experience, something that I'll have to tell my kids forever.”

Consummating it was Mountcastle, who launched a 3-2 Matt Andriese fastball high off the Green Monster to break a scoreless tie. To that point, Means had spent much of the afternoon trading zeros with Eovaldi, who overwhelmed the Orioles in their 2020 opener and then held them to four hits over 5 1/3 innings Friday. Pedro Severino’s leadoff infield single helped chase Eovaldi in the sixth, before Andriese walked Trey Mancini and Hernández booted a potential double-play ball to load the bases.

The error opened the door for Mountcastle’s bases-clearing hit, and Anthony Santander’s eighth-inning RBI single provided insurance for Tanner Scott and César Valdez to record the final six outs. Means also benefited from three highlight-reel defensive plays from converted third baseman Rio Ruiz at second, in his third career start at the position.

“How about that?” Means said. “That was unbelievable.”

Thrust into emergency second base duties because of the Orioles’ last-minute spring decision to part ways with Yolmer Sánchez, Ruiz found himself in Friday’s lineup largely for the same reason Mountcastle did: his bat. Starting him in the cleanup spot on Opening Day speaks to the how the Orioles view Mountcastle, their No. 5 prospect per MLB Pipeline, after he hit .333 with five homers and an .878 OPS in 35 games down the stretch in 2020. The shortened ‘20 season left him four at-bats shy of shedding his rookie eligibility; no matter whether he claims Rookie of the Year hardware or not, Mountcastle could easily become the rare player to receive votes for the Award in two separate seasons.

All that though, as Mountcastle implied Friday morning, is talk for much later in the summer. But its part of the conversation around the Orioles as they embark on 2021 because of how they’ll use this season to further set the foundation for their rebuild now several years in the making. If nothing else, Friday provided a snapshot of what an ideal '21 might look like if that all breaks right: Mancini back in the fold, Means blossoming into a legitimate ace and Mountcastle growing into a middle-of-the-order mainstay.

M&M … &M? It has a ring to it.

“Because he’s got poise, because he’s got confidence, he’s going to be a really good hitter in this league,” Hyde said. “He is a threat when he swings the bat.”