Clay Buchholz throwing Sept. 19 in Fenway Park. (Charles Krupa / AP)

Buchholz, who has not pitched in a big-league game since June 16 because of a back problem, will remain with the team in Baltimore rather than travel to Florida for an Instructional League game. Buchholz told WEEI Radio he could be activated for tonight’s game against the Orioles. You know, the game that has the wild-card hopes of the Red Sox riding on it.

Buchholz is recovering from a stress fracture in his lower back and most likely would be available for relief. Since June 16, he has thrown bullpen sessions and an 18-pitch inning Tuesday, according to Jon Lester is expected to start for the Sox.

Chen, according to a report by Fox’s Ken Rosenthal, might be the choice to pitch a tiebreaker game Thursday, if there is one, and the team is exploring an extremely late trade with the Kansas City Royals.