The move is retroactive to Aug. 2, so Craig hopes he can play for the Red Sox again on Aug. 17.
"Honestly, it's just a little tweak. Obviously, they want to do their evaluations and make sure everything's good," said Craig. "I just got here. Obviously, I want to be out there, and they want me to be out there, but now's a good period to just evaluate things and move forward."
Craig dealt with serious foot woes late last season and into the World Series, so the Red Sox want to take every precaution.
"There's the likelihood [we'll have] a second opinion with Dr. [Robert] Anderson," said manager John Farrell. "The fact is, he reached for the bag the other night and turned his ankle, and we just want to be clear and get as much information to determine if there's no correlation between the previous injury and this one. So we're still in a fact-finding stage right now."
To replace Craig on the roster, the Red Sox purchased the contract of outfielder Corey Brown from Triple-A Pawtucket.
A non-roster invitee to Spring Training, Brown has hit .226 with 14 doubles, two triples, 16 home runs, 39 RBIs and 27 walks in 83 games for the PawSox.
In another roster swap, knuckleballer Steven Wright was sent back to Pawtucket after spending just one game on the roster. Righty Heath Hembree, acquired from the Giants in the trade for Jake Peavy, was recalled from Pawtucket.
"He's a guy that's got a sinker/slider," said Farrell. "Likes to compete. The two outings that he's made in Pawtucket for us were consistent with the reports coming over from the Giants. Just now getting to know him firsthand."
Ian Browne is a reporter for MLB.com. Read his blog, Brownie Points, and follow him on Twitter @IanMBrowne. Teddy Cahill is a reporter for MLB.com. Follow him on Twitter at @tedcahill. This story was not subject to the approval of Major League Baseball or its clubs.