The grand finale of the old Big East has officially begun.

No. 5 Georgetown (22-5, 13-4 Big East) faces off with No. 16 Syracuse (23-7, 11-6 Big East) this afternoon in what — barring a conference tournament matchup — will be the archrivals’ final meeting as conference opponents.

The Hoyas had been on an 11-game tear that propelled them to the top of the conference and earned them top-seed status in many an NCAA bracket forecast. But a scrappy Villanova team with a penchant for upsets knocked off the streaking Blue and Gray Wednesday night, and Georgetown now faces an ultimatum for its rivalry-defining game against the hated Orange: Win, or give up the regular-season title.

The loss at Villanova toppled Georgetown from its perch above the Big East fray; it now finds itself in a three-way tie with Marquette and Louisville for the top spot. Due to tiebreaker rules, however, a win Saturday would give the Blue and Gray the No. 1 seed at Madison Square Garden.

The high-stakes scenario adds some spice to a game that might have been, well, as ho-hum as the finale of the fierce rivalry could get.

While Georgetown has soared to the top of the standings, Syracuse has plummeted. Reeling from an embarrassing loss to the Hoyas at the Carrier Dome, the Orange dropped two straight games to Marquette and Louisville before rebounding with a win over conference punching bag DePaul. The resulting scenario, in which Syracuse had played itself out of contention for the title, was hardly the stuff of promoters’ dreams.

But with the end of Georgetown’s winning streak comes an added urgency for the Hoyas. They aren’t just playing for the last word in the rivalry — they’re playing for the chance to go out on top in the old Big East’s last season.

Now they just have to win the game.

That task doesn’t look anywhere near as daunting as it did a month ago. Despite Wednesday’s loss, the Blue and Gray have proven themselves to be an immovable defensive force and efficient offensive machine, capable of competing with any team in the country. Super soph Otto Porter Jr.’s one-man evisceration of the Orange on Feb. 23 showed that Jim Boeheim’s vaunted two-three zone is far from invincible, and an ugly three-game slide in Syracuse only backed up that idea.

The Hoyas, however, can’t rely completely on Porter Jr. to beat the Orange once again. He’ll need to play well for Georgetown to stay in the game, but no one can realistically expect another 33-point masterpiece from the star forward. This means veteran floor general Markel Starks and freshman gunner D’Vauntes Smith-Rivera will need to play a much bigger role in breaking the zone.

One point of consolation for Hoyas fans is that Syracuse almost certainly won’t employ a similar defensive strategy to the one that forced the Blue and Gray into 23 turnovers Wednesday at Villanova. Jay Wright’s high-pressure man-to-man defense looks nothing like the Orange zone, and it’s hard to see Boeheim making such a dramatic adjustment so late in his career.

On the other end, expect Syracuse to come out with a well-rehearsed attack for Georgetown’s zone — the strategy of jacking up 28-foot treys at the end of the shot clock didn’t work out so well for Brandon Triche and the rest of the Orange marksmen. John Thompson III will likely switch up defensive looks early and often to confuse his opponents and ensure more bad shots.

The ultimate verdict? If Georgetown plays defense as phenomenally as it did in the Carrier Dome clash two weeks ago, the Hoyas will likely walk out of the Verizon Center as victors and Big East regular season champions.

But if thirty-plus years in the world’s best basketball conference have taught us anything, it’s that games like this are inherently unpredictable. And if Syracuse pulls off the road upset, well, there isn’t a college basketball fan in the country who wouldn’t want a rubber match at Madison Square Garden.