OAKLAND -- Before his 80-game PED suspension, Frankie Montas was the A's best starting pitcher, and quite frankly, one of the best starters in all of baseball.

In 15 outings, the right-hander went 9-2 with a 2.70 ERA, notching 97 strikeouts in 90 innings. While he won't be eligible for the postseason, Montas will be allowed to return for the A's final five games of the regular season, beginning Sept. 25.

Those games are likely to be critical, with Oakland, Tampa Bay, and Cleveland all battling for two AL wild-card spots. Montas, 26, could certainly give the A's a nice boost in that final week.

"We've had Frankie working out in Arizona since he got suspended," A's general manager David Forst told Chris Townsend on A's Cast. "He's thrown a number of simulated games down at Fitch Park (in Mesa), basically pitching four or five innings every fifth day."

Forst also mentioned that Montas is eligible for a rehab assignment starting on Sept. 10. If either Triple-A Las Vegas or Double-A Midland advances to the next round of the minor-league playoffs, he would make a start on Tuesday.

When Montas does return to Oakland, the A's could either use him as a starter for one of the final five games or as a reliever to help their struggling bullpen.

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"We expect those to be meaningful games and we've kept him stretched out in case we want him to start one of those five," Forst told Townsend. "But Frankie has obviously pitched out of the pen in his career as well. Sure, run him out there five nights in a row, why not? But no, when we get closer, we'll figure out the right role for him. But he's going to be active for those five games and he'll be a part of the group."

Even though Montas won't pitch in the postseason this year, he could definitely help the A's get there.