The series opener against the host Houston Astros on Thursday resulted in a loss for the Mariners as a team, but the Seattle rotation took a step forward.

Mariners right-hander George Kirby made his season debut in a 9-2 defeat against the Astros.

Seattle will try to level the four-game series on Friday.

Kirby missed the opening 48 games with right shoulder inflammation but showed flashes of his stellar form on Thursday despite allowing five runs on six hits in 3 2/3 innings. He struck out four and walked one.

His comeback bolsters a strong but injury-hampered rotation, with Seattle getting additional good news about right-handed starters Bryce Miller and Logan Gilbert.

Miller (right elbow inflammation) and Gilbert (right elbow flexor strain) were placed on the injured list in mid-May and late April, respectively. Both are expected to throw on Friday in Houston.

“They’re going to be able to throw early in a simulated kind of situation (Thursday) and looking forward to getting those guys some work (Friday) as well,” Mariners manager Dan Wilson said. “Our guys are getting closer and closer to being healthy, and (Thursday) was that first step with George.”

Right-hander Emerson Hancock (1-2, 6.21 ERA) has the starting assignment for the Mariners on Friday. He allowed one run on six hits and one walk with three strikeouts over 4 2/3 innings against the San Diego Padres on Saturday but did not factor into the decision of a 4-1 victory.

Hancock is 1-0 with a 2.91 ERA in four road starts this year. Seattle won each of those games.

Hancock has faced the Astros once previously in his career. He tossed two-plus scoreless innings and allowed two hits and recorded two strikeouts in a no-decision on Aug. 20, 2023.

Rookie right-hander Ryan Gusto (3-2, 4.65) is the scheduled starter for the Astros. It will mark his sixth start and 12th appearance on the season, with Gusto posting a 2-2 record and 6.33 ERA as a starter and a 1-0 mark with a 0.93 ERA out of the bullpen.

In his most recent start, on May 12 against the Kansas City Royals, Gusto allowed seven runs on seven hits and three walks with two strikeouts over 2 1/3 innings in a 7-5 home loss. On Saturday, he worked a scoreless inning of relief against the Texas Rangers, issuing two walks in the Astros’ 5-1 defeat.

Gusto worked a scoreless inning against the Mariners on April 8, issuing one walk and earning a victory in relief, the first of his career. Saturday will mark his first start against Seattle.

The Astros put Ronel Blanco on the 15-day injured list on Thursday and announced that the right-handed starter would seek a second opinion on his inflamed pitching elbow.

Blanco joins right-handers Hayden Wesneski (pending Tommy John surgery) and Spencer Arrighetti (broken right thumb) on the IL, further depleting an already short-handed rotation.

“Around the league, it’s a head scratcher,” Astros manager Joe Espada said of pitcher injuries. “It’s happening not only here but throughout the league.

“I’m sure that we’re always looking for ways to keep our guys healthy. All organizations are doing the same, but this is part of the game. We have to work through this and fight through this. This is a team that has shown resiliency for many, many years. We are prepared to put ourselves in a position where we can continue to move forward. That’s our challenge right now.”

–Field Level Media