Feldman will miss some time after being placed on the 15-day disabled list, leaving Collin McHugh to make his Astros debut Tuesday night as Houston looks to deal the host Seattle Mariners an eighth straight loss.
The veteran right-hander was scheduled to start this contest, but the Astros (6-14) placed him on the DL on Monday with biceps tendinitis. Feldman, 2-1 with a 1.69 ERA, is expected to miss at least two outings after giving up five runs and nine hits in six innings of Thursday's 5-1 loss to Kansas City.
Feldman allowed one run and seven hits in 20 2-3 innings over his first three starts.
"I was pitching fine, so I wasn't overly concerned about anything," Feldman said. "My arm felt fine. After the last game, it just never recovered like it had been.
"Going on the DL is not what I wanted to do, but sometimes you've got to do what's best for the team, and hopefully we'll get this thing right and be back as soon as possible."
McHugh will make his first start since September with Colorado after being called up from Triple-A Oklahoma City to replace Feldman. The right-hander, though, is 0-8 with an 8.94 ERA in 15 major league appearances - nine starts - for the New York Mets and Rockies since 2012.
The Astros will be looking to back McHugh with a similar offensive performance as Monday's series opener, as they tied their season high for runs and ended a seven-game losing streak with a 7-2 victory.
Matt Dominguez went 2 for 3 with three RBIs and Marc Krauss homered and drove in two runs for Houston, which has outscored the Mariners 34-9 while winning five straight meetings.
The Astros were outscored 35-14 during their skid. Chris Carter, who is hitting .123 with 26 strikeouts in 14 games, was given Monday off, though manager Bo Porter said he'll be back in the lineup for this contest.
"I'm not doing really much to help the team," Carter told the Astros' official website. "I'm in a pretty important part of the lineup and have been DH'ing. Hitting is pretty much the only thing I'm doing and I'm not doing that well."
Seattle (7-12) hasn't done much offensively during its losing streak, scoring two runs or fewer five times after striking out a season-worst 14 times Monday. Abraham Almonte's two-run double tied the score in the fifth, but Dustin Ackley went 0 for 4 with three strikeouts and Justin Smoak also went hitless in four at-bats.
''When you lose seven in a row you're looking for a lot of things ... you're looking for pitching you're looking for defense, you're looking for hits,'' manager Lloyd McClendon said. ''One thing I tell the players, the only people that will right the ship is us.''
The Mariners will try to end their skid with help from Erasmo Ramirez, who has mostly struggled to start the season.
Ramirez (1-2, 7.50) failed to get more than 12 outs for the second time in his last three starts Thursday, giving up five runs and six hits through two frames of Seattle's 8-6 loss to Texas. Opponents are hitting .324 off him.
''I didn't execute the pitches,'' Ramirez said. ''Maybe that was the point of this game. I know I'm better than that.''
The right-hander has made one start against the Astros, giving up two runs and striking out seven in 5 2-3 innings of a 3-2 victory Aug. 29.