As the Houston Astros battle to stay in the playoff chase, it's not clear whether two starters who helped them to the postseason last year will do the same this year.

Left-hander Dallas Keuchel, who has been sidelined with shoulder inflammation, said Monday that he is not ready to resume throwing. He's been out since Aug. 27 and said Friday that he would reassess his situation Sunday. That re-evaluation has been pushed back to Wednesday.

Right-hander Lance McCullers, meanwhile, hasn't thrown off a mound as he tries to come back from a sprained elbow suffered Aug. 2.

Dallas Keuchel is not ready to throw after being sidelined with shoulder inflammation since late August. AP Photo/Eric Christian Smith

"It's going to depend on where we're at as a team and where they're at," Astros manager A.J. Hinch said Monday, according to the Houston Chronicle. "Our idea is to continue positive progress with these guys and not set a timeline or a necessary deadline for them to have to meet. Otherwise we'll threaten further injury. One more setback for any of these guys, and it's over."

Keuchel, 28, won 20 games and the Cy Young last season for an Astros team that advanced to the division series, losing to the eventual World Series champion Royals. McCullers, 22, was counted on to be a big part of the Astros this season after an encouraging rookie campaign.

Astros starters are struggling at the wrong time. Houston is 3½ games out of the second wild card and 4-6 in its past 10 games. Hinch acknowledged that the team is walking a tightrope with the two pitchers.

"They're not doing enough to be ruled in or out," Hinch said, according to the newspaper. "McCullers is the closest guy, but you can play catch all you want -- until you get on the mound, it's when you really get serious about pitching. Keuchel's not throwing yet, so there's certainly some concern on both of theirs for different reasons because of where we are on the schedule, but we'll go day-to-day."