Urias, formerly the organization's top starting-pitching prospect, made three scoreless relief appearances as a September call-up in his return from shoulder surgery, a procedure that kept the left-hander out for more than a year.
Dodgers manager Dave Roberts said lefty reliever Scott Alexander, whom Urias replaced on the roster, is "healthy," adding that Urias was chosen because "we like his pitch mix, the weapons that he has to attack the lefties and the righties in their lineup."
Roberts said Urias can be available to pitch more than one inning and that he is comfortable using him in back-to-back games, even though Urias hasn't done that all season.
"It wouldn't be an extended back-to-back," Roberts said. "But the value of Julio to come in and get one to four or five outs, for us, with our bullpen construction -- we feel comfortable with that."
Urias for Alexander was the only change on the Dodgers' roster from their NL Division Series against the Atlanta Braves.
The Brewers' only change was to add lefty Xavier Cedeno to their bullpen after carrying just 11 pitchers in the first round against the Colorado Rockies. Cedeno, 31, pitched in 15 games during the regular season for Milwaukee after being acquired from the Chicago White Sox, posting a 1.13 ERA.
Outfielder Keon Broxton was left off the Brewers' roster after serving as a reserve outfielder against the Rockies. Broxton, 28, hit just .178 during the regular season, but he is one of the Brewers' fastest players and top pinch-running options.
Urias was on his way to becoming a top-of-the-rotation starter for the Dodgers until undergoing surgery to repair a torn capsule in June 2017.
He struggled at times in his return to the minors late this season, ultimately allowing seven runs on 10 hits and seven walks in a span of 11 2/3 innings. But he later threw four scoreless innings with the Dodgers, allowing only one baserunner while striking out seven batters. His fastball touched 97 mph.
Urias, who hasn't pitched in a game since Sept. 30, was given ample rest in between outings and pitched only in low-leverage situations.
The intensity will naturally ratchet up in the postseason.
Roberts noted how Urias was able to channel his emotions as a 20-year-old in the 2016 postseason and said "the health component" is of utmost importance.
"We've talked to the trainers, the doctors and Julio himself and feel that the strength and where he's at physically, that we're not compromising anything," Roberts added. "When you put those two things together, we feel really good about our decision."