And so the roller-coaster ride continues.

Georgetown (13-4, 3-3 Big East) laid a 63-47 beating on No. 24 Notre Dame (15-4, 3-3 Big East) Monday night in South Bend, Ind., where the Irish had won 47 of their last 49 games.

Sophomore forward Otto Porter Jr. played the entire 40 minutes, scoring 19 points and grabbing nine rebounds to lead the Blue and Gray to their third win in four games.

Freshman point guard D’Vauntes Smith-Rivera added 14 off the bench.

“We are fortunate that they only counted us for one loss, with the way that thing went,” Notre Dame Head Coach Mike Brey said.

Clad in their black alternate jerseys, the Hoyas took the court only 48 hours after an embarrassing loss at South Florida, which was winless in Big East play at the time. Add in sophomore forward Greg Whittington’s continued ineligibility and nationally ranked Notre Dame’s formidable home-court advantage, and this game had all the makings of another disappointment.

But against all odds, Georgetown came out with guns blazing. After going down 2-0 on Irish forward Jack Cooley’s two free throws, the Hoyas went on a 7-0 run and never trailed again. They shot better than 53 percent from the field and 46 percent from three-point range, and no defensive scheme the Irish came up with seemed to slow the visitors down.

Notre Dame struggled mightily to score against the smothering Blue and Gray defense, posting season-lows in total points (43) and field goal percentage (35). Though Georgetown Head Coach John Thompson III employed his formidable 2-3 zone defense less often than usual — likely due to Whittington’s absence — theHoyas’ man-to-man was clearly sufficient.

“I think our defensive effort was really good today,” Thompson III said. “We were on the same page and we made things difficult for them, and that’s just hard work.”

The win was particularly surprising considering the personnel issues facing Georgetown for much of the game: On top of Whittington’s ineligibility, both junior forward Nate Lubick and sophomore center Mikael Hopkins got into early foul trouble and were only available sparingly. Hopkins eventually fouled out after playing only 15 minutes.

Junior backup center Moses Ayegba came to the Hoyas’ rescue, though, grabbing 10 rebounds in relief and pestering Cooley, a Wooden Award candidate, into a 4-of-11 shooting night.

“Moses Ayegba was a presence on the boards, and I thought he did a good job on Cooley, who’s one of the better post players in our conference,” Thompson III said.

The Irish didn’t go down without a fight, however. A 16-4 run from the hosts closed the gap to only three points with 12 minutes to play, as the game began to resemble Saturday’s loss to USF.

But rather than falling apart as they did in Tampa, the Hoyas crushed the comeback attempt with ease. Porter Jr. and Indiana native Smith-Rivera took turns nailing clutch jumpers, sparking an 18-0 run that silenced the Joyce Center crowd.

“It was an eerie feeling, to be out of it for the last 10 minutes of the game in our home building,” Brey said. “It was creepy. It was eerie. It was not pleasant. It was very foreign territory for all of us, fans included.”

The Blue and Gray have five days off before their biggest test since November, a Saturday showdown with No. 5 Louisville in the nation’s capital. If Monday’s Georgetown team shows up rather than last weekend’s, fans should be in for a good time.

Tip-off is scheduled for noon.