MLB Insider Breaks Down Astros’ 2026 Rotation Plan After Imai Signing

The Houston Astros have plenty of starting pitching to choose from, and an MLB insider has revealed what the team is most likely to do.

Jan 5, 2026; Houston, TX, USA; Houston Astros pitcher Tatsuya Imai talks during a press conference at Daikin Park. | Troy Taormina-Imagn Images

The Houston Astros are losing their ace in Framber Valdez. However, the Astros were able to sign the top Japanese starting pitcher, Tatsuya Imai. The agreement will make him a co-ace with Hunter Brown in Houston.

With Imai and Brown at the top of the rotation, Houston has five other starting pitchers to choose from when rounding out the rest of their starting pitching group. However, the team may not go with just five starters for the 2026 season. A six-man rotation is the more likely scenario.

Per Joel Sherman of the New York Post, the Astros are likely to use that six-man rotation model.

The Astros are likely to start the season with a 6-man rotation after adding Japanese star Tatsuya Imai to the mix.#MLBNHotStove | @Joelsherman1 pic.twitter.com/DznEH0Ymtz

— MLB Network (@MLBNetwork) January 7, 2026

Why Use a Six-Man Rotation?

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There were a few reasons mentioned when talking about the usage of a six-man rotation in Houston.

"You have a Japanese pitcher who is used to pitching once a week in Imai. So this makes it more comfortable for him," Sherman said on MLB Network's Hot Stove.

The Astros want to make the transition to the states as seamless as possible for Imai. If using a six-man rotation is a way to do that, then that should be done. Imai has loads of talent, but the workload in Japan is less than what might be expected in the MLB.

The most innings Imai has thrown in a season overseas is 173.1. For reference, that would put him 29th, right behind his Japanese counterpart, Yoshinobu Yamamoto. It would also rank him third on the Astros behind Valdez and Brown.

With Valdez gone, Houston needs someone who can go deep into games and stay healthy. Imai might be that guy, but the challenge will be helping him adjust to the MLB workload.

Sherman also mentioned that the MLB schedule is becoming too much for just five starters in the rotation. 25 games in 27 days becomes a lot for those pitchers to go every fifth day. In this modern era of baseball, teams are going to slot in six starters.

Who Rounds Out the Astros Rotation?

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Cristian Javier and Spencer Arrighetti are two pitchers who missed time in 2025 with their respective injuries. They are both expected to be healthy enough to pitch a full season in 2026. Lance McCullers is another interesting pitcher in the rotation, but his injury history is very concerning.

The other two pitchers to consider are Mike Burrows and Ryan Weiss. The Astros acquired Burrows via trade with the Pittsburgh Pirates, and they brought Weiss back to the MLB after he spent some time in Korea.

Of these five pitchers, the Astros will have to pick three or four to round out their starting rotation. All signs are pointing towards Houston using six starters, so four of these right-handers will join Imai and Brown in the starting group.

Javier, Arrighetti and McCullers seem to be three locks for the rotation, despite their injury history. That leaves Burrows and Weiss. Burrows started 19 games in 2025 for Pittsburgh, while Weiss made 30 dominant starts in Korea. Of those two, Weiss seems to be the more likely candidate, with Burrows filling a long-relief role that will include some spot starts.

No matter the case, Houston has options to choose from. More will be found out during spring training, but expect the Astros to try a six-man rotation.

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