PITTSBURGH -- Jermaine Couisnard dropped a career-high 40 points against his former team as No. 11 seed Oregon toppled No. 6 South Carolina 87-73 in first-round NCAA Tournament action on Thursday.

Couisnard spent three seasons with the Gamecocks before transferring to Oregon ahead of the 2022-23 season. He shot 14-of-22 from the floor on Thursday, making 5 of 9 from beyond the arc and adding six assists and four rebounds.

"This was my grandmother's first game, so I was happy to see her, being able to drive out here and being able to get to watch me play," Couisnard said. "... It was me just being a competitor. I know those guys have a great team over there, Coach Lamont (Paris) did a wonderful job this year, and it was me just showing my will."

N'Faly Dante provided 23 points, six rebounds, two blocks and two steals for the Ducks (24-11), who continued their postseason romp after beating three teams in three days to win the Pac-12 tournament and earn an automatic NCAA bid. Oregon will face No. 3 seed Creighton on Saturday.

The Ducks outshot the Gamecocks 59.6 percent to 44.6 percent. Couisnard and Dante helped Oregon rack up 36 points in the paint and 24 on free throws.

Meechie Johnson poured in 24 points, Ta'Lon Cooper had 15 and B.J. Mack scored 13 for South Carolina (26-8), which suffered a field-goal drought of 8:21 at the end of the first half and could not recover.

Jacobi Wright and Johnson made back-to-back 3-pointers for South Carolina midway through the first half to break a 14-14 tie. Couisnard responded with a triple and a tough jumper.

Couisnard said postgame that he heard Wright, his former teammate, say "It's cash" after making his 3 -- and that's what got him going.

"That's my little brother, though," Couisnard said. "It was nothing personal."

That prompted an 18-2 stretch for Oregon that included 11 straight points. Couisnard scored seven more himself, including an athletic three-point play, and his next layup capped the outburst to make it 32-22 Oregon.

After Jackson Shelstad (11 points) scored for the Ducks with less than three seconds on the clock, Cooper's heave from way beyond halfcourt banked in at the buzzer to cut South Carolina's halftime deficit to 34-29.

"I didn't have no thought" the shot could go in, Cooper said. "Just kinda let it go, see where it did and it went in and I just kept running."

Oregon restored its double-digit margin on Shelstad's steal and score at the 17:11 mark of the second half, and the Ducks embarked on another long run. Dante dunked a lob pass from Jadrian Tracey, and a short time later, Dante blocked a shot that let Couisnard run out in transition for a pull-up 3.

The Ducks were up 55-37 when the damage was done.

Johnson and Mack hit 3-pointers to help the Gamecocks claw back within 11, but Couisnard kept answering. The closest South Carolina would come was 67-57 after Cooper's triple with 6:51 left. Couisnard made his fifth 3-pointer of the day on the next possession.

Couisnard's 39th and 40th points came at the foul line during the final minute.

--Adam Zielonka, Field Level Media