Garrett Crochet and Tanner Houck are both making meaningful progress in their respective rehabs, raising the possibility that two pitchers Boston once envisioned near the top of its rotation could instead become late-season weapons out of the bullpen.

Garrett Crochet (shoulder) threw a 16-pitch bullpen session on Friday.

At a time of year when the attrition of pitching hits most teams, the Red Sox are fortunate enough to have a couple of key arms in Garrett Crochet and Tanner Houck working toward a possible return to action later this month.

BOSTON — One-hundred-fifteen days after he last threw a pitch for the Red Sox, staff ace Garrett Crochet spent part of his Tuesday afternoon playing catch on the Fenway Park field. He tossed a baseball back and forth with a team staffer in right field,

Garrett Crochet (shoulder) threw off the mound again before Tuesday's game against the Mariners.