With only a few days before the Astros open the regular season on Thursday against the A’s in Oakland, the composition of the Opening Day roster is all but set. The last piece to the puzzle is center fielder Myles Straw, who’s expected to be cleared from quarantine within the next day. Once that happens, the club will announce the final roster.

The Astros will carry 13 position players and 13 pitchers, but the roster figures to fluctuate early in the season, with pitchers Pedro Báez and Jake Odorizzi expected to be added at some point in April.

Here’s the latest roster projection for Opening Day:

Catcher (2): Martín Maldonado, Jason Castro
The Astros will have one of the most experienced catching tandems in the big leagues with Maldonado and Castro. If Houston wants to carry a third catcher, which is unlikely, the club has Garrett Stubbs on the 40-man.

First base (1): Yuli Gurriel
Gurriel hasn’t swung the bat particularly well this spring, but there will be no cause for alarm unless it bleeds into the regular season. The Astros have several options who could play first base if Gurriel needs a day off or is at designated hitter, including Aledmys Díaz.

Second base (1): Jose Altuve
Altuve has put aside any concerns about the throwing problems that plagued him in the playoffs last year. He’s hit a couple of home runs this spring, including one from the leadoff spot. Altuve has batted leadoff for much of the spring and is expected to be there on Opening Day.

Third base (1): Alex Bregman
Bregman was slowed by a sore left hamstring in the first three weeks of camp, but holding him back was strictly precautionary. He hasn’t had nearly as many at-bats as the other starters in Grapefruit League games, but he got plenty on the back fields earlier in camp and has been crushing the ball.

Shortstop (1): Carlos Correa
Correa has had a nice spring at the plate, and says he’s continued to benefit from the changes he made in his mechanics in the playoffs last year. Of course, he made news last week when he said he turned down a six-year, $120 million contract extension from the Astros earlier this spring.

Outfield (4): Kyle Tucker, Michael Brantley, Myles Straw, Chas McCormick
While Brantley (left), Straw (center) and Tucker (right) are the starters, the fourth outfield job goes to McCormick, who’s on the 40-man roster. He was on the playoff roster last year in the American League Wild Card Series and AL Division Series, but he didn’t play.

Utility (2): Aledmys Díaz, Robel García
The injury-prone Díaz navigated around some hamstring soreness late in camp, but he appears to be healthy heading into the season. Abraham Toro and García, both switch-hitters, battled for the last infield spot, but the club wants Toro to play every day in the Minor Leagues, giving the nod to García.

Designated hitter (1): Yordan Alvarez
Alvarez, the 2019 AL Rookie of the Year Award winner, didn’t play in a Grapefruit League game until March 14, as the Astros took it easy after he had surgery on both knees in August. He appears to be over the knee problems that have plagued him. Still, manager Dusty Baker appears reluctant to play Alvarez in left field and risk injury and losing his bat.

Starting pitchers (5): Zack Greinke, Lance McCullers Jr., Jose Urquidy, Cristian Javier, Luis Garcia
Baker has set his rotation for the first four games of the season, with Greinke, Javier, McCullers and Urquidy pitching in that order. The fifth start of the season will be by either Garcia or Brandon Bielak, but we’re leaning toward Garcia. Odorizzi will join the rotation a week or so into the season and bump Garcia or Bielak to the bullpen.

Relievers (8): Ryan Pressly, Joe Smith, Enoli Paredes, Brooks Raley, Ryne Stanek, Blake Taylor, Brandon Bielak, Bryan Abreu
The Astros will be without Báez (delayed throwing because of a COVID-19 positive test) and Andre Scrubb (shoulder) to start the year. With that, Pressly, Smith, Paredes, Raley, Stanek, Abreu and Taylor are locks at this point. Bielak or Garcia -- whoever doesn’t get the fifth starter spot -- will be in the ‘pen.