Randy Mower (5-5) went seven innings, allowing five runs, to earn the win. Charlotte's Patrick Lawson fell to 5-3 with the loss. He allowed 13 runs in 5.2 innings.
Saint Joseph's (15-27-1, 8-14 Atlantic 10) got things started in the top of the first as Plakis led off the game with his second home run of the season.
Charlotte (29-18, 13-10 Atlantic 10) scored a pair in the bottom half of the frame as Rob Lyerly hit his 10th round tripper of the season, a two-run shot to left.
The Hawks then exploded for 10 runs in the top of the second as the frustrations of an 11-game losing streak seemed to come to a head. After leaving the bases loaded in the first, SJU made no such mistake in the second as all nine players in the starting lineup reached base and scored before a single out was recorded. Mike Blahusch led off with a single and went to third on a failed pickoff attempt. Joe Cook walked to put runners on the corners for Plakis, whose second home run in as many at bats put the Hawks back on top, 4-2. Mike Coleman followed by extending the school record that he set on Friday night with his 14th hit by pitch of the season. A David Valesente single and a Dewey Oriente walk loaded the bases before Brian Hartsell plated Coleman by drawing a walk. That set the table for Ryan McDonald, who poked a single to center to score Valesente and make it a four-run game. The next batter was Pursino, who took Lawson's 1-2 pitch down the left field line and over the wall for his first career grand slam and a 10-2 Saint Joseph's advantage.
Blahusch reached base for the second time in the inning when he was hit by a pitch for the record 37th time of his career. He stole second and then advance to third on a groundout by Cook, the first out of the inning. A passed ball scored Blahusch with the 10th run of the inning before Plakis and Coleman were retired to end the biggest single-inning outburst of the season.
The 49ers got one back in the bottom of the third, but SJU increased its lead to 13-3 in the fourth. McDonald led off with a triple and come home on a groundout by Pursino. After Cook hit a two-out double to right, Plakis singled him in for his fifth RBI of the game.
Grant Bomann hit a solo home run in the bottom half of the fourth to cut the lead back down to nine. It would be reduced to eight in the sixth on a single by Justin Wilson.
SJU finished off the scoring in the top of the eighth when McDonald was hit by a pitch for the second time in the game and eventually came around to score on a double play grounder by Cook.
Mower moved into fifth on the SJU all-time innings pitched list, reaching 223.0 for his career. He struck out six while walking just one. Dominic Favazza pitched two scoreless innings to finish off the game.
Saint Joseph's will look to secure the series victory on Sunday afternoon as the teams will play the rubber match of the three-game series. First pitch is slated for noon. Live stats will be available via Gametracker at SJUHawks.com