The Panthers scored in the first inning in both games, forcing Youngstown State to play from behind both times.
Nick Unes hit a two-out, two-run single in game one to put UWM up 2-0, and Luke Meeteer's two-out single in the fifth made the score 3-0.
YSU stranded a pair of runners in each of the first two innings and left the bases loaded in the fifth inning. The Penguins loaded the bases again in the seventh as Jonny Miller singled, Lorenzo Arcuri walked and Andrew Kendrick was hit by a pitch. Gerrad Rohan then ripped a three-run double to right center that cleared the bases and tied the score at 3-3.
Joel Hake came on with two runners on in the bottom of the seventh inning to keep the game tied, but Cole Heili hit Hake's first pitch of the eighth over the fence in left center to give the Panthers the lead.
The Penguins had a chance in the ninth but were turned away. Alex Larivee led off with a single but was caught stealing, and Kendrick and Rohan followed by reaching on a hit batter and single, respectively. Jake Tuttle struck out Billy Salem and Trey Bridis consecutively to end the game.
Rohan had three of YSU's seven hits in the opener, and the Penguins drew seven walks. YSU stranded 12 runners in the one-run loss.
YSU starter Joe King allowed three runs on seven hits and five walks in 6.2 innings, and Heili's homer was the only run that Hake allowed.
Milwaukee led 1-0 two batters into game two after a Billy Quirke single and an Aaron Buban triple, and the Panthers went on to score all six of their runs in the first two innings.
Youngstown State stranded a pair of runners in the fourth and sixth innings, and the Penguins left the bases loaded in the seventh.
YSU starter Jeremy Quinlan allowed all six runs on 10 hits in six innings, but he surrendered just two hits after the second inning to give the Penguins a chance to rally. Chris Sparks pitched two shutout innings in relief.
Milwaukee's Elijah Goodman shut out the Penguins over six innings, and Zach Brenner came on to pitch the final two innings for the Panthers.
Youngstown State will play another doubleheader on Sunday at UIC. First pitch of game one at Curtis Granderson Stadium is set for 2 p.m. Eastern.