CLEMSON, S.C. (AP) — Cade Klubnik heard the boos and saw the scoreboard with No. 25 Clemson trailing Charleston Southern. He knew before anyone told him, things had to change.

“I just had to come back and refocus. I just had to play like me or let external factors, the fans and what people say hurt my soul,” Klubnik said. “I just didn’t let that happen.”

The sophomore rallied his team with a career-high 315 yards and four touchdowns in a 66-17 rout that sure didn’t look like one in the opening half.

Antonio Williams had touchdown grabs of 10 and 5 yards while Phil Mafah ran for two short touchdowns as the Tigers (1-1) improved to 38-0 all-time against teams from the Football Championship Subdivision.

The Tigers and Klubnik bounced back from an opening-week meltdown, losing 28-7 at No. 21 Duke. But miscues and poor execution from that game were on display the first two quarters here.

Clemson restored order with four third-quarter touchdowns — three on TD passes from Klubnick.

Clemson’s Beaux Collins had seven catches for 137 yards, including a 69-yard TD after a pass over the middle where several Charleston Southern defenders were sprawled on the field behind him.

Clemson continued to dominate statistically in the second half against Charleston Southern and finished with 679 yards to 73 for the Big South Conference. team.