The Tigers faced the prospect of dropping the season series for a fourth straight year after falling at their home field to the Gamecocks, 6-0, on Friday night. But Schmidt shut down South Carolina's lineup on five hits, allowing only a pair of solo homers to Max Schrock and LB Dantzler.
Duggar's two-run single off reliever Adam Westmoreland put Clemson up 5-0. Duggar also scored his team's first run.
Clemson closer Matt Campbell worked the final two innings. He struck out Graham Saiko for the final out, flexing in celebration as the Tigers ended a three-game series losing streak.