BOSTON -- The Astros, as expected, opted to carry a 12th pitcher on their roster for the American League Championship Series against the Red Sox, which gets underway on Saturday at Fenway Park. Houston will have 13 position players.Astros manager AJ Hinch said on Friday that rookie outfielder Myles Straw

BOSTON -- The Astros, as expected, opted to carry a 12th pitcher on their roster for the American League Championship Series against the Red Sox, which gets underway on Saturday at Fenway Park. Houston will have 13 position players.

Astros manager AJ Hinch said on Friday that rookie outfielder Myles Straw and veteran right-hander Will Harris, both of whom were on the AL Division Series roster against the Indians, would be replaced by right-handed relievers Hector Rondon and Joe Smith, giving him an eight-man bullpen.

"Hector and Joe, both are very valuable relievers, very high-end relievers for us," Hinch said. "It's a little bit of ... you have to pick the group of guys. And we're going with the guys that we feel best match up for different looks for different parts of their batting order. Not an easy exercise."

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There was some thought about keeping Straw, a fast runner, over outfielder Jake Marisnick , but Marisnick has made several big plays at Fenway Park the last few years, and he has more experience, in addition to his top-notch defense.

Harris gave up one run and one walk in his only inning in relief in Game 3 of the ALDS, but that performance had no bearing on the decision to leave him off the ALCS roster, Hinch said.

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"Will is the odd man out by numbers, not by skill," Hinch said. "I think Josh James came in and became a viable weapon. He's got length. He's got a 100 mph [fastball] in his back pocket. He's got a good breaking ball, a good changeup."

If the Astros advance, they can change their roster prior to the World Series.

Starting pitchers

Justin Verlander , who is 12-6 with a 3.08 ERA in his career in the postseason, will start Game 1, with Gerrit Cole starting Game 2 on Sunday. Cole struck out 12 batters in beating the Indians in Game 2 of the ALDS. Hinch hasn't announced the rest of his rotation, but it's expected that Dallas Keuchel would start Game 3 on Tuesday at Minute Maid Park and Charlie Morton will go in Game 4 on Wednesday. Morton didn't pitch in the ALDS because the Astros swept the Indians.

Relievers

Rondon and Smith, the Astros' two offseason acquisitions for the bullpen, were added to the ALCS roster after being left off the ALDS roster. They'll be joined in the bullpen by right-handers Roberto Osuna , Thomas Pressly , James, Lance McCullers and Collin McHugh , and lefty Tony Sipp . Sipp and James didn't pitch in the ALDS, so the Astros have five pitchers who didn't work in the previous series, including Morton.

Infielders

The Astros' infield is as stable as it gets with Yuli Gurriel at first base, Jose Altuve at second base, Carlos Correa at shortstop and Alex Bregman at third base. Correa hit .180 in 133 at-bats after coming off the disabled list with a back ailment on Aug. 10, and he struggled in the ALDS before hitting a three-run homer in Game 3 on Monday.

Outfielders

George Springer , the 2017 World Series MVP, is joined by veteran Josh Reddick , Marisnick, Tony Kemp and the versatile Marwin Gonzalez , who's an infielder by trade but has been starting in left field in the playoffs.

Designated hitters

Tyler White started twice in the ALDS against the Indians, with Kemp starting Game 3. Evan Gattis is also an option to start at DH.

Catchers

Martin Maldonado and veteran Brian McCann are the catchers. Expect Hinch to use his catchers like he did in the ALDS, with Maldonado catching Verlander and Cole and McCann catching Keuchel. If the Astros have the lead in a game McCann is starting, he's likely to bring in Maldonado to control the Boston running game.

Here is the complete roster:

Catchers(2)

Brian McCann

Martin Maldonado



Infielders (5)

Jose Altuve

Alex Bregman

Carlos Correa

Yuli Gurriel

Marwin Gonzalez



Outfielders (4)

George Springer

Josh Reddick

Jake Marisnick

Tony Kemp



Designated hitter (2)

Evan Gattis

Tyler White



Pitchers (12)

Justin Verlander

Gerrit Cole

Dallas Keuchel

Charlie Morton

Roberto Osuna

Ryan Pressly

Tony Sipp

Josh James

Lance McCullers Jr.

Collin McHugh

Hector Rondon

Joe Smith

Postseason roster rules

Teams submit a 25-man roster prior to each round of the postseason comprised of postseason-eligible players. A club may request permission from the Commissioner's Office to replace a player injured during the course of a series, but the injured player is then ineligible for the rest of that round and the subsequent round, if there is one. A pitcher may only be replaced by another pitcher, and a position player by a position player.

Teams carry extra players throughout the postseason in the event of injuries, and those players, as well as players on the disabled list, can be in the dugout during games, within reason.

Brian McTaggart has covered the Astros since 2004, and for MLB.com since 2009. Follow @brianmctaggart on Twitter and listen to his podcast.