Otto Porter scored 19 points on 7-of-10 shooting and grabbed nine rebounds, as Georgetown shut down No. 24 Notre Dame in a 63-47 decision at Purcell Pavilion.
D'Vauntes Smith-Rivera chipped in 14 points for the Hoyas (13-4, 3-3 Big East), who shot 53 percent from the field and hit 7-of-15 from behind the arc to complement their stifling defense.
Georgetown, coming off a loss at South Florida on Saturday, held the No. 1 shooting team in the Big East to 35 percent shooting.
Jerian Grant led Notre Dame (15-4, 3-3) with 13 points, Pat Connaughton went for 12 and Jack Cooley added 10 with 10 rebounds, but it wasn't enough in the Fighting Irish's third loss in four games.
Notre Dame cut into a 15-point deficit with 10 straight points early in the second half, and even pulled within three, 40-37, on a Connaughton layup with 12 minutes to go.
Smith-Rivera silenced the suddenly loud home fans with a 3-pointer and hit another from long range during an 18-0 flurry that took all the energy out of the building.
"It was an eerie feeling to be out of it for the last ten minutes of the game in our home building," Notre Dame head coach Mike Brey said. "It was creepy. It was eerie. It was not pleasant. It was very foreign territory for all of us, fans included."
A pair of Jabril Trawick buckets ended the seven-minute stretch for a 58-37 advantage that was never threatened over the final five minutes.
The Hoyas started strong and never really cooled off. They shot 13-of-22 (59 percent) from the field in the first half and even connected on eight straight attempts at one point to open up a 21-8 cushion midway through the stanza.
"It was key to come out from the tip, get that quick start and jump right on," Porter said. "That's kind of what our game plan was, and we just went from there."
Notre Dame pulled within four before going the final five minutes without scoring. The subsequent 9-0 run to end the half, capped by Porter's bucket in the lane, gave the visitors a 34-21 lead.
The Irish, who came in first in the conference in field goal percentage (.505), shot 30 percent (6-of-20) in the first half and found themselves down 36-21 after Georgetown made the first field goal after the break.
Georgetown came in second in the Big East in scoring defense by allowing 56.3 points per game ... Trawick finished with seven points, six assists and six boards ... Notre Dame shot 2-of-16 from 3-point range and was outrebounded, 35-24.