ANN ARBOR, Mich. -- No. 12 Michigan unleashed a six-home run monsoon against Michigan State on Friday to win 21-2 in five innings at the Wilpon Complex, home of Alumni Field.

The 21 runs marked a season best for the Wolverines and the most against MSU. The Wolverines extended their winning streak to 15 games and home win streak to nine games.

The Spartans started the scoring in the top of the first, but U-M turned that into a distant memory with a six-run second inning and 13-run third inning.

U-M pushed one run across in the bottom of the second before freshman Sierra Romero bashed a grand slam to take a 5-1 lead. It was Romero's second grand slam of the season. Senior Amy Knapp plated the sixth U-M run of the inning on a single up the middle, her second hit of the inning.

The Wolverines were relentless in the bottom of the third, scoring 13 runs and hitting four home runs. Sophomore Lauren Sweet started the inning with her fourth home run of the season. Later in the inning with two runners on, the Spartans walked Romero to load the bases. One batter later, senior Ashley Lane delivered two runs batted in on a single.

Lane was the first of seven consecutive Wolverines to reach base, including junior Lyndsay Doyle, who hit her first career home run, knocking in three runs.

With two outs, freshman Kelsey Susalla and junior Taylor Hasselbach hit back-to-back pinch hit home runs. Susalla's blast cleared the grandstand in right field, and Hasselbach's homer went out to dead center field. The roundtrippers marked the fourth back-to-back home runs for the Wolverines this season and the first time in pinch hitting situations.

After three innings, the Maize and Blue held a 19-1 advantage against the Spartans, the most runs scored this season.

In the fourth inning, the Wolverines added two more runs on the first career home run by junior Katie Luetkens. Luetkens' blast into the right field grandstands was the sixth for U-M, a season high, and pushed the squad past 20 runs for the first time since 2000.

Sophomore Haylie Wagner was the beneficiary of all the runs. She pitched four innings, striking out five and giving up just one run on two hits. She picked up her 12th win of the season. Freshman Alice Fitzpatrick pitched the fifth and final inning.