The Mountaineers scored five runs on five hits with two errors in the fourth inning to take a 5-1 lead over the Cougars.
The outburst was all Appalachian State (24-5, 9-2) needed as Mountaineer starter Seth Grant (6-1) went eight innings, allowing just two runs on four Cougar hits. Matt Pegler (5-2) picked up just his second loss of the season as he allowed five runs, four earned, and 10 hits in four innings pitched.
The win kept the Mountaineers unbeaten at home and in first place in the Southern Conference, while College of Charleston (21-11, 11-6) lost its fourth game in a row.
Junior Tyler Jackson was the lone offensive bright spot for the Cougars as he homered and doubled in his first two at-bats after getting the start at first base.
Appalachian State was led by Tyler Zupcic's 3-for-3 performance with a triple that allowed him to round all the bases after a throwing error. Will Callaway hit a three-run home run and Tyler Tewell tallied two hits.
Jackson broke the deadlock in the top of the third inning with an opposite-field solo home run, his fourth of the season to put CofC up 1-0.
Appalachian broke the game open in the bottom of the fourth inning as the Mountaineers scored five runs on five hits, including two doubles and a triple with two CofC errors, to take a 5-1 lead over the Cougars. Jeremy Dowdy, Trey Holmes, Hector Crespo and Zupcic all tallied RBIs in the inning.
The Mountaineers added to the lead in the bottom of the sixth inning when Callaway hit a three-run home run to left field to push ASU's lead to 8-1.
College of Charleston scored a run in the top of the eighth inning when pinch-hitter Daniel Aldrich reached on an error by the second baseman. Bradley Goodson launched a double to the wall in right center that scored Aldrich from first and put the score at 8-2.
The final game of the series between Appalachian State and College of Charleston is scheduled for Sunday at 1 p.m.