NORTH CHARLESTON, S.C. — Joe Chealey scored 22 points and top-seeded Charleston defeated No. 8 seed Drexel 66-59 on Sunday to advance to the Colonial Athletic Association Tournament semifinals.

Charleston (24-7) will play fourth-seeded William & Mary — an 80-66 winner over No. 5 seed Towson later Sunday — on Monday.

Grant Riller added 17 points in surpassing 1,000 in his career and Jarrell Brantley had 12 points and 11 rebounds, his 21st career double-double, for the Cougars, who shared the regular-season title with Northeastern but got the No. 1 seed by virtue of a season sweep of the Huskies.

Trailing by nine, Chealey hit a pair of 3-pointers to start a 20-5 run to take a 59-53 lead with 2:38 remaining. The Dragons (13-20) were within four with a minute to go but Riller hit a 3-pointer and Chealey two free throws to go up nine.

Kurk Lee scored 15 points, Tramaine Isabell had 14 points and 12 rebounds and Austin Williams 12 points for Drexel.