Weeks is day-to-day, and will be re-evaluated before Sunday's game.
"We'll see what happens tomorrow," said Brewers manager Ron Roenicke. "But we're fortunate that, at least right now, that there's no break. Sometimes there's a little hairline [fracture] there later. But right now we're fortunate."
Weeks was hit by a pitch on his wrist and hand leading off the bottom of the 13th, the second time he was hit in the game. His 97th and 98th career hit by pitches extended Weeks' club record.
After having the injury examined briefly, Weeks remained in the game, eventually scoring the game-winning run for the Brewers.
Had he left the game, things would have gotten interesting for Milwaukee, which had just two available players remaining: starting pitchers Marco Estrada (who was in the bullpen) and Yovani Gallardo, who was scheduled to pinch-hit later in the inning.
"Yo was going to go to left, Braunie was going to short and Izzy to second," Roenicke said, referring to left fielder Ryan Braun and shortstop Cesar Izturis.