After opening this season in Boston's bullpen, Workman was optioned to Pawtucket on April 9, where he was used as a starter.
"I feel like I've been throwing pretty well," said Workman, who was 3-1 with a 5.12 ERA. "My numbers aren't the best right now, but I feel like I've been throwing the ball better than the numbers have shown and I feel pretty confident about it right now."
Workman started three games for the Red Sox last year, going 1-1 with a 2.45 ERA. He lost a start to the Rays on July 22, but pitched well, giving up seven hits and two runs over six innings.
"I definitely will be going over scouting reports and stuff like that to get ready, but there was a little bit of familiarity because I've seen them a few times, but we'll definitely need a refresher for that," said Workman.
Workman feels he's at his best as a starter.
"I feel real good with it," said Workman. "Starting, I've been able to throw my changeup a little bit more, work a two-seamer in. Those are things I didn't really do much out of the bullpen, but I've been able to work on them. I feel confident in them right now."
When the Red Sox activate Workman, they will likely option right-hander Alex Wilson back to Pawtucket. Wilson was recalled on Friday.
Doubront was placed on the disabled list earlier this week with a left shoulder strain.
Ian Browne is a reporter for MLB.com. Read his blog, Brownie Points, and follow him on Twitter @IanMBrowne. This story was not subject to the approval of Major League Baseball or its clubs.