Mercy senior guard Collette Hailey banked in an off-balance 30-footer with one second left in regulation to tie the score, but third-ranked and host Institute of Notre Dame prevailed over the Magic, 63-61, for its first girls basketball victory over Mercy since 1996.
Senior forward Caroline Wesley scored 15 points and grabbed 17 rebounds for the Indians (5-2) and senior forward Colby Lee hit three of four free throws in the final minute of overtime to seal the victory in the Interscholatic Athletic Association of Maryland A Conference game.
The Magic, which staged a 15-point fourth-quarter rally to end regulation at 54-54, fell to 4-2.
The Indians led by nine at halftime and seemingly had the game in hand after three quarters, but 16th-ranked Mercy crept back into it behind Hailey, who finished with 29 points.
"We just let up in the fourth quarter," IND coach Herb Hoelter said. "We were cruising. We let up and let them back in the game."
IND played the final eight minutes without its leading scorer, sophomore guard Chandrea Jones, who fouled out late in regulation after scoring 17 points.
Mercy led briefly in overtime, 60-59, but about 15 seconds after the Magic took the lead, Wesley drained a 10-footer and the Indians never trailed again.
The win was IND's first in its past 11 tries against Mercy.
No. 1 St. Frances 66, Catonsville 26: Junior forward Angel McCoughtry had 21 points, 15 rebounds and five steals to lead the Panthers (6-1) past the visiting Comets in a nonconference matchup.
No. 13 Arundel 48, St. Mark's (Del.) 47: Amanda Hernandez hit the game-winning shot with six seconds to play as the visiting Wildcats (3-0) knocked off Delaware powerhouse St. Mark's.
Hernandez had 11 points and Jessica Collins added 13 for the Wildcats.
No. 15 McDonogh 41, No. 10 Seton Keough 35: The host Eagles (2-3, 1-2 in IAAM A Conference) emerged from a back-and-forth contest with the victory, putting away the Gators behind senior guard Jessy Morgan's game-high 13 points.
Seton Keough guard Andrea Bustamante (11 points) hit two three-pointers in the third quarter to give her team the lead.
Mount de Sales 43, No. 18 St. Mary's 42: The senior forward tandem of Heather O'Donnell and Hailey Tucker combined for 16 points and 12 rebounds as the host Sailors (1-2) overcame a 20-9 second-quarter deficit to edge the Saints.
Boys
No. 4 Mount St. Joseph 65, No. 18 Cardinal Gibbons 51: Junior center Will Thomas scored 23 as the Gaels (5-0) beat the host Crusaders (6-3) in a Baltimore Catholic League game.
No. 5 Lake Clifton 81, #419 22: Led by senior forward Tavon Nelson's 22 points and 15 rebounds, the host Lakers (3-1) rolled.
No. 7 Mervo 80, City 39: Junior guard Chester Frazier had 24 points, 10 rebounds and 10 assists to lead the host Mustangs (3-3) past the Knights in a Baltimore City contest.
No. 9 St. Frances 83, Centennial 51: Four Panthers scored in double figures, led by Gordon Brown's 13 points, as visiting St. Frances (6-1) downed the Eagles (3-3) in a nonconference game.
No. 11 McDonogh 57, Avon Farm School (Conn.) 51: The Eagles (4-1) erased a 12-point deficit and outscored Avon 21-11 in the fourth quarter to advance to the semifinals of the Ray Mercer Invitational at the Hill School in Pennsylvania.
Junior guard Jon Brick scored 15 points for the Eagles, who will face Episcopal Academy (Pa.) tonight.
No. 13 Walbrook 60, Edmondson 58: The visiting Red Storm erased a 14-point deficit in the fourth quarter to take the lead with less than three minutes to play, but Rocky Coleman's 5-for-7 performance from the free-throw line down the stretch enabled the Warriors (5-2) to escape with the win.
Coleman, a junior forward, scored nine of his game-high 21 in the fourth quarter.
No. 14 Aberdeen 65, Havre de Grace 53: Junior guard Philip Brown scored 15 as the Eagles (4-0) overcame a halftime deficit and beat the host Warriors (2-1) in a Harford County league game.