The 35-year-old is hitting .254 with eight home runs and 23 RBI.
In 2017, Braun was twice placed on the injured list with a left calf strain, landing on the shelf a second time just days after he was activated following the first stint.
He followed that up with two trips to the IL in 2018 and finished with a .254 batting average, 20 home runs and 64 RBI in 125 games.
The 2011 National League MVP can be a big-time contributor when healthy, but he hasn't appeared in more than 140 games since 2012.
Braun is a six-time All-Star and face of the franchise, and an extended absence could hurt the Brewers' power potential.
The five-time Silver Slugger has hit 25 or more home runs in a season on eight occasions, and he drove in 100 or more runs in five straight seasons from 2008 through 2012.
His production has been inconsistent in recent years, but Braun did put up a .305 batting average with 30 homers and 91 RBI in 2016, which marked his best campaign since 2012, when he was the runner-up to Buster Posey in the NL MVP race.
Milwaukee has a talented lineup, and its depth should help balance the potential loss of Braun.
If he is forced to miss some games, though, Lorenzo Cain, Christian Yelich and Ben Gamel will likely comprise the starting outfield.
The Brewers have significant question marks in their starting rotation, which forces them to score a lot of runs in order to win.
If Braun is not available, it will be more difficult for Milwaukee to successfully engage in slugfests.