The Terps reached the 30-win threshold for the first time since 2013 with 11 games remaining in the regular season.
The Terps won the series with back-to-back wins over the Hawkeyes on Friday, but couldn't complete the sweep.
Trinity Schlotterbeck and Keira Bucher combined to allow just three hits as the Terps evened up the weekend series.
The Terps scored 22 runs in the three-game set against the Spartans.
The Terps defeated North Dakota earlier on Friday in their home-opener.
A strong start from Courtney Wyche and timely hitting pushed the Terps to victory.