The winning layup capped a wild last sequence that saw The Webb School's
Bree Robinson tie the game at 50 with a corner 3-pointer with five seconds left. Sidwell's
Leah Harmon took the inbounds pass, split a double team near midcourt and found Donovan, a Duke commit, leaking out early for the wide-open layup and the two-point victory.
Donovan, battling foul trouble for much of the night, was held to eight points, but none bigger than the deuce near the buzzer.
Khia Miller led the Quakers with 12 as Harmon added 11 and
Kendall Dudley chipped in nine.
Webb School started the season ranked in the MaxPreps Top 25 and the Feet made a case for themselves to re-enter the rankings after a 20-point win Friday over No. 5 La Jolla Country Day and the valiant effort against Sidwell.

Sidwell Friends' Jadyn Donovan, seen earlier this year at Nike TOC, scored the game-winning bucket on Saturday to help the No. 2 Quakers to a 52-50 win over The Webb School at the GEICO Girls Basketball Invitational. (Photo: Darin Sicurello)
Sidwell led 46-37 after Harmon's 15-footer before Collins, who scored all 10 in the second half, drained a jumper with just over two minutes to play. Biriyk second 3-pointer of the night brought the Feet within six at 48-42 before Collins and LSU commit
Angelica Velez combined for five straight and Webb trailed 48-47.
Harmon, a junior, hit both ends of the one-and-one for the three-point lead, which led to the wild finish.
Both teams used a relentless defense to force turnovers as Webb School had 10 giveaways and Sidwell turned it over seven times in the first half.
The Quakers jumped out to a 13-5 lead on a 3-pointer from Miller and bumped the lead to 15-8 on two Donovan free throws. But Webb School wrestled back a lead with a 9-1 run stretching from the first into the second quarter on a pair of buckets from Robinson, a triple from Collins and a fast break bucket from Biriyk.
But Sidwell answered with a bucket from Dudley in the paint and 3-balls from Miller and Dudley sandwiched around a Robinson triple to take a 24-20 edge with 3 minutes before the break. The end of the half saw
Tatianna Stovall drop a bucket before Cannon and
Ava Yoon trade 3-pointers as Sidwell took a 27-25 edge into the locker room.
Breya Cunningham dropped 36 as the Torreys rebounded from their loss to Webb School on Friday. The Arizona commit was 15 of 18 from the field and added 17 rebounds in the victory.