Brown, the third catcher on the active roster, had a .225 average with five home runs and 24 RBIs in 52 games at Triple-A Pawtucket.
"We have four or five days with an extra roster spot until [Buchholz] pitches, and we just wanted to use it to our advantage," said Francona.
Pitcher Fernando Cabrera was designated for assignment and pitcher Felix Dubront was optioned, making space for reliever Manny Delcarmen to be reinstated from the 15-day disabled list and Brown to be recalled.
While Brown hasn't been told what his specific role will be, Francona said he would most likely catch Sunday's finale against the Rangers.
Brown wasn't recalled sooner, even with injuries to Victor Martinez and Jason Varitek, because he was hurt as well. Brown injured his left thumb three weeks ago on a play at the plate and was in a cast for a week.
"We will see. He hasn't played a ton because of that thumb. We will see," Francona said. "The one thing [Kevin Cash] does really well is run the game, so we will try to balance that the best we can."
Since his thumb healed, Brown had caught four games. He also caught many of the Red Sox pitchers in Spring Training.
"I don't really know about how it is going to go, but I will be ready to play every day and if my name is on the card, I'll go out there and do my best," said Brown.