OAKLAND -- The comeback trail for Chris Bassitt is nearly complete.

Prior to Monday’s four-game series opener against the Mariners, Bassitt threw a 30-pitch bullpen session at the Coliseum, marking his fourth throwing session over the past nine days, as he continues to build himself back up. The next time he takes the mound could come in an actual game for the A’s.

“We’ll see how he does tomorrow,” A’s manager Bob Melvin said. “If he feels good tomorrow, we’ll let you know what’s next.”

Melvin added that he was “optimistic” that Bassitt could be activated off the 10-day injured list and appear in a game “at some point” this week. The only question is whether that appearance would come as a starter or in a relief role.

“I think that’s something we still need to talk about,” Melvin said. “How long we think he can go. Whether or not we feel like it should be in a starting role or coming out of the bullpen.”

Bassitt earned the first All-Star selection of his career at age 32 and was making a strong bid for the AL Cy Young Award until he was hit in the face by a line drive on Aug. 17 during his start against the White Sox in Chicago. At that point, Bassitt ranked among the top of the league in most pitching categories, having gone 12-4 with a 3.22 ERA and 154 strikeouts in 151 innings pitched across 25 starts.

Whatever the role, having their ace return to pitch at all this season would certainly be an emotional boost for the A’s in the midst of a tight playoff race. Entering Monday, Oakland trailed the Blue Jays by two games for the second American League Wild Card spot.

A’s add relief help in Feliz

Seeking a lift for their bullpen over the final two weeks of the regular season, the A’s claimed right-handed reliever Michael Feliz off waivers from the Red Sox on Monday. Catcher Aramis Garcia was designated for assignment to make room on the 40-man roster, though a corresponding move will still have to be made to add Feliz to the active roster.

The overall numbers this season have not been great for Feliz, who will be joining his fourth club this season. He’s combined to post a 7.32 ERA in 20 relief appearances for the Red Sox, Pirates and Reds. However, the A’s are intrigued by Feliz’s 30 percent career strikeout rate (324 strikeouts in 246 1/3 innings) over seven big league seasons.

“I believe he throws pretty hard and misses some bats,” Melvin said. “You look at our overall numbers in the bullpen and we’re probably not the hardest-throwing bullpen in the league. Anytime we can improve that with a better fit, that’s something we’re pretty consistent in doing.”