Shortly before boarding a plane to Boston for their Opening Day tilt against the Red Sox, the Orioles on Thursday finalized the group that’ll be suiting up for that game. The club executed a flurry of transactions in setting its 30-man Opening Day roster ahead of the 2020 season, with few surprises -- but several new faces coming into the fold.

Of the spots still in limbo as of this week: Pat Valaika was added to the 40-man roster and made the team in a utility role; Cedric Mullins played his way back to the Majors with a strong Summer Camp; and injuries helped righties Evan Phillips and David Hess sneak into bullpen roles.

The O's also reinstated Dwight Smith Jr. from the COVID-19 injured list, while placing ace John Means (left arm fatigue) and right-handed relievers Hunter Harvey (right elbow discomfort) and Dillon Tate (right forearm) on the 10-day injured list to begin the year. All are backdated to Monday, meaning they will be eligible to return July 30, seven games into the season.

That’s possible for both Means and Harvey, whose issues the team has characterized as minor. Tate, the club’s No. 27 prospect, has not resumed throwing since being hit in the right arm with a comebacker about two weeks ago.

Here is the Orioles' full 30-man roster:

Catcher (2): Pedro Severino, Chance Sisco

Severino came into his own offensively last year in his first chance at everyday at-bats, hitting 13 homers in 96 games. Sisco made swing changes back home in California this winter after hitting .210 with a .729 OPS in 59 games last season. This is a big year for the former second-round Draft pick.

First base (1): Chris Davis

With Trey Mancini out for the year and No. 4 prospect Ryan Mountcastle still on the Minor League side, Davis’ roster spot is as secure as its been in a long time. He’s the starting first baseman, and the O’s are hoping for a bounceback season from the former home run champion.

Second base (1): Hanser Alberto

Alberto was one of the best stories of the 2019 Orioles, emerging as a .305 hitter after languishing on the waiver wire. He assumes the everyday second-base job this year with Jonathan Villar in Miami, and Alberto likely moves to the top of the lineup against left-handed pitching, which he crushed at a near-historic rate last summer.

Third base (1): Rio Ruiz

How much more is there in Ruiz’s bat? The O's want to find out after the third baseman slugged .544 over a 29-game stretch last August and September, then arrived in camp this year with a tweaked swing and packing 10 pounds of extra muscle. Ruiz also posted strong defensive metrics in the first half of last season before wearing down a bit down the stretch. On a team looking for its young players to get better, Ruiz is a candidate to do so.

Shortstop (1): José Iglesias

Seeking stability up the middle, the Orioles inked the veteran Iglesias to a one-year, $3 million free-agent deal with a club option this winter. A former All-Star with Detroit in 2015, Iglesias developed a reputation as one of the game’s more skilled defenders over eight seasons with the Red Sox, Tigers and Reds. He enjoyed his best offensive season last year in Cincinnati, hitting .288 with 11 homers and 59 RBIs.

Utility (2): Andrew Velazquez, Pat Valaika

Once the O's lost Richie Martin (right wirst surgery) and Stevie Wilkerson (left ring finger fracture), the lane was clear for Velazquez and Valaika to make the team in utility roles. Velazquez is a speedster who can play shortstop and center -- and nearly every other position on the field. Valaika has shortstop experience but is more of a corner infielder who can provide right-handed pop off the bench.

Designated hitter (1): Renato Núñez

Núñez got his chance at extended Major League at-bats last year and ran with it, slugging 31 homers with 90 RBIs. The Orioles are hoping improved consistency and plate discipline lead to even better production this season.

Outfielders (5): Austin Hays, Anthony Santander, Dwight Smith Jr., DJ Stewart, Cedric Mullins

The O's were unsure whether Smith would be ready for Opening Day after reporting late to camp due to COVID-19. It turns out he is ready, and he will likely jostle Stewart for playing time in left. Hays assumes the everyday center-field job and will probably hit leadoff more days than not. Santander recovered without a hiccup from COVID-19; he is back to play right field every day and hit third or fourth in manager Brandon Hyde’s order. Mullins is back in the Majors after his lost 2019 season, playing his way onto the roster with a strong Summer Camp.

Starting pitchers (5): Alex Cobb, Wade LeBlanc, Asher Wojciechowski, Tommy Milone, Kohl Stewart

Without Means, the Orioles open the year with a rotation of Milone, Cobb, LeBlanc and Wojciechowski, in that order. Look for Stewart to take the ball in Means’ place, then probably slide into a swingman role.

Relievers (11): Mychal Givens, Richard Bleier, Paul Fry, Shawn Armstrong, Miguel Castro, Tanner Scott, Cody Carroll, Cole Sulser, Travis Lakins, David Hess, Evan Phillips 

Hunter Harvey’s 11th-hour bout with right elbow discomfort opens a spot for Hess, who can both start and be used in long relief. Givens is back as the primary high-leverage option, likely to handle most save opportunities. Bleier can swap in occasionally, if the matchup is favorable, as the veteran lefty is healthy again and looking for a bounceback year.

Armstrong, Fry, Castro and Scott return to setup roles, with Castro and Scott emerging as potential breakout candidates. Carroll was acquired in the Zack Britton deal in 2018 but missed all of last year with back trouble, while Sulser is a strikeout artist who Baltimore found on the waiver wire and Lakins provides additional depth. Phillips benefits most from the layoff; he was sidelined with right elbow soreness when Spring Training was halted, but has earned an Opening Day roster spot.