Caroline Hartley scored 11 of her 16 points in the fourth quarter as fifth-seeded Scarborough defeated No. 4 South Portland 50-34 in a Class AA South girls’ basketball quarterfinal Wednesday at South Portland’s Beal Gymnasium.

The Red Storm (9-10) will take on No. 1 Thornton Academy in the semifinals next Wednesday at Cross Insurance Arena.

South Portland (9-10) got out to a fast start, as Anna Brown made three 3-pointers for an 11-6 lead. Scarborough, though, answered with an 8-0 run to take the lead for good.

The Red Storm led 16-15 after one quarter, then forced seven South Portland turnovers in the second quarter and held the Red Riots without a point for nearly seven minutes as they stretched their advantage to 26-19 at halftime.

Four points from Brown late in the third helped South Portland cut the deficit to 31-28 heading to the fourth quarter, but the Red Storm clinched the win at the foul line.

Emerson Flaker chipped in with 12 points and Ellie Rumelhart had 10 for Scarborough.

Brown led all scorers with 18 points before fouling out late.