OAKLAND -- Lefty Brett Anderson is making progress toward a return, but the A's rotation remains in flux in the meantime.
Anderson, who was placed on the disabled list Tuesday with a left forearm strain, threw from flat ground on Sunday and could get on a mound as soon as Monday, per A's manager Bob Melvin.
Left-hander Sean Manaea, meanwhile, is struggling to even raise his arm as he nurses a shoulder injury and is unlikely to pitch again this season. The A's, who must operate under this assumption, have since experimented with a different pitching plan, utilizing the "opener" formula in a game that went awry Saturday.
It's unclear whether the A's will implement the same practice again, but there's certainly potential for it Tuesday; they have yet to name a starter for their meeting with the Yankees that night. Right-handers Chris Bassitt and Frankie Montas, who are still with Triple-A Nashville, could be in play to pitch in the game -- either to start or follow an opener.
The A's, who started reliever Liam Hendriks in Saturday's 8-7 loss to Seattle, went through an Oakland-record nine pitchers in as many innings.
"We'll continue to evaluate that," Melvin said. "It didn't go great for us last night, but we're trying to be as creative as we can to do what we think is the right thing to do."
A member of Melvin's Opening Day rotation, right-hander Andrew Triggs, threw a simulated game in Stockton on Saturday and could begin a rehab assignment at some point this week. Triggs, attempting to return from right arm nerve irritation, could be a relief option later this month.