Cook, who gave up a season-high seven runs on eight hits in just 2 1/3 innings in the first game of a doubleheader on Sunday, will throw bullpen sessions both Tuesday and Wednesday nights while the team is playing a three-game series at Washington.
"He wants to, and quite frankly I think it will be good for him because of the amount of time he had off prior to his last start," said Rockies manager Jim Tracy regarding Cook, who had missed his previous start while nursing an injury to his right big toe and had gone 10 days between starts.
In a 10-3 loss to Florida on Sunday, Cook saw his record drop to 10-5 and his ERA rise from 3.93 to 4.31.
Cook, whose out pitch is a sinker, never got into a groove on Sunday and Tracy theorized that the extra rest may have been part of the cause for that.
"Obviously, mechanically he was not in synch, but also some of the things that might be attributable to that was that he was too strong," Tracy explained. "A sinkerball pitcher that's too strong sometimes starts throwing the ball up in the zone, and we dealt with an awful lot of that [on Sunday]."
Lisa Winston is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.