The Tigers, behind Dale Davis' 26 points and 17 rebounds, overcame a 19-point deficit and snapped the nation's longest winning streak at 22 games, beating No. 12 La Salle, 79-75, Saturday in the second round of the East Regional at Hartford, Conn.
Clemson held Simmons, La Salle's All-American forward, scoreless for 11:44 in the second half and the 17th-ranked Tigers turned a 55-44 deficit into a 75-65 lead with 1:40 left.
The victory followed a 49-47 first-round win over Brigham Young in which Davis had only two points and Clemson survived by scoring the last nine points.
Clemson (26-8) will meet Connecticut in the round of 16 Thursday night in East Rutherford, N.J.
"I didn't kick or throw anything at halftime," Clemson Coach Cliff Ellis said. "I just reminded them that we had been down 17 at the half to Georgia Tech, 13 to Maryland and 11 to Virginia and we came back each time.
"The defense came through for us just like it had all year, and our offense picked up. We needed to go on the attack."
Simmons had 28 points for La Salle, but Davis helped hold the All-American scoreless as Clemson took control. Simmons' three-point basket with 12:36 left put the Explorers ahead, 55-44, but he didn't score again until 1:22 remained when his basket merely cut Clemson's lead to 75-67.
It was two different games for Simmons, who had 32 points and 16 rebounds in a first-round victory over Southern Mississippi.
Simmons ended his college career with 3,217 points, 32 short of the NCAA's second-highest total of 3,249 by Freeman Williams of Portland State. Pete Maravich of Louisiana State is the NCAA record-holder with 3,667 points.
The Explorers took a 41-22 lead on Simmons' stuff with 2:43 left in the first half and led, 43-27, at halftime.
Clemson, though, used its superior strength and size to rally. Davis and Elden Campbell, both 6-foot-11, dominated the inside and Sean Tyson scored 17 points.
Milko Lieverest's basket and Randy Woods' three-point shot gave La Salle a 60-55 lead, but a layup by Tyson started a 10-point run in which the Tigers took the lead for good.
Doug Overton's jump shot made it 65-62, but the Explorers got no closer as Davis began a 5-0 run with a stuff.
A three-point shot by Woods cut the lead to 70-65 with 2:01 remaining, but La Salle called a timeout when it had none left, and Davis made two the two technical foul shots. Three consecutive free throws by Cash gave Clemson its biggest lead, 75-65, with 1:40 left.