Manager Craig Counsell said Braun was day to day, and he acknowledged that tightness in Braun's back kept him out of Thursday's starting lineup, too.
"It kind of was bugging him Wednesday, just enough that it's time to rest a little bit, or back off," Counsell said.
Braun, 33, has missed time in past years due to tightness in his lower back, sidelined for short periods of time in both 2015 and '16.
"We had a couple occasions where he missed a couple of days throughout the season, so it's similar," Counsell said.
In five games, Braun is batting .250 with a homer. He scored the winning run in Milwaukee's 2-1,11-inning win over the Cubs on Friday night, racing home on a wild pitch. Counsell said Braun did not further aggravate his back when sliding into Chicago reliever Mike Montgomery at the plate.
It is the second injury suffered by a key member of the team this week. Opening Day starter Junior Guerra was placed on the 10-day disabled list after suffering a strained right calf Monday against Colorado.
Franklin, a switch hitter, was used mostly at second base in Spring Training with Tampa Bay, Counsell said, he but played 18 games in left field this past season.
"I like to get left-handed hitters in against [Chicago starter Kyle] Hendricks, so it's an opportunity to get Nick in there," Counsell said.
Joe DiGiovanni is a contributor to MLB.com and covered the Brewers on Saturday.