HOUSTON -- The last thing that Astros manager AJ Hinch wanted to do Wednesday night was put first baseman Tyler White back on the mound for the fourth time this season. Having to pull White out after throwing 38 pitches -- and giving up six runs to the Pirates in the ninth inning of a 14-2 blowout loss -- only made matters worse and underscored the dire state of Houston’s pitching staff.

Hinch walked off the mound with White after he recorded just two outs, patting him on the back and telling him he was sorry for putting him in that position. Max Stassi, a catcher making his first appearance on any mound, got the final out, but the treads are wearing thin on the Astros’ overworked bullpen.

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A second consecutive abbreviated start by lefty Framber Valdez, who allowed six runs and eight hits in three innings and was optioned to Triple-A Round Rock postgame, put more stress on an Astros bullpen that has been struggling to cover innings for much of June. Chris Devenski gave Houston three innings Wednesday and Hector Rondon and Collin McHugh gave it one each before Hinch sent White to the mound in an 8-2 game.

“It’s brutal. It’s embarrassing,” Hinch said. “I feel bad for Whitey. I apologized to him on the way off the field because I never want to use him. It’s not funny. I know it’s entertaining for the masses when you see something unique ... but I think it sucks. I don’t want to hurt him. It’s way too many pitches. Just an unfortunate night when [the Pirates] launch balls off the back of the building because it’s a position player. It’s unfortunate.”

A corresponding roster move will be announced prior to Thursday’s series finale, but the Astros are working through their options with two games looming next week at Coors Field, the most hitter-friendly park in the Majors. Off-days on Monday and Thursday could allow them to go with a four-man rotation in the short term.

“I pitched two position players, so that tells you where our bullpen is,” Hinch said. “We’ll have to take a look at all of our options and see how we navigate. We have four more games in a row [before a day off] and the two games at Coors Field that are looming which are always difficult. And then a couple of days off sprinkled in.”

The Astros sent down pitchers Rogelio Armenteros and Reymin Guduan on Tuesday, and they must stay in the Minor Leagues at least 10 days unless there’s an injury. Among pitchers on the 40-man roster with big league time at Triple-A include Dean Deetz, Brady Rodgers and Corbin Martin on the injured list. So is top pitching prospect Forrest Whitley, who’s on a throwing program in Florida and not pitching in games.

What’s more, lefty reliever Cionel Perez was optioned to Round Rock on June 19 after allowing 10 runs in eight innings in three games with the Astros earlier this month. He isn’t an option.

Valdez, 25, came to Spring Training competing for a spot in the rotation, but he wound up making the club as a reliever while trying to refine his control. He was moved to the rotation and was making his fourth start Wednesday, but after giving up 11 runs in 6 1/3 innings in his past two starts, the Astros were forced to send him down.

“I understand why they did it and I understand what I need to do to get better, so that's what I’ll be focusing on,” Valdez said. “It’s been frustrating, but at the same time I know I need to improve my two-seamer and improve my command to get back here and help the big league club.”

Hinch is saving his three most reliable relievers -- Roberto Osuna, Ryan Pressly and Will Harris -- for close games, but even their workload has been stretched. The lack of quality depth is why Hinch has turned to White four times in blowouts this year. Stassi ended the ninth by getting Josh Bell to ground out, but it was hard for anyone in the home dugout to enjoy this night.

“It was cool to have a first appearance, but in those circumstances it’s never really that fun,” Stassi said. “You’ve got to do what you’ve got to do for the team and it’s part of my role right there.”