WASHINGTON — For the first time in school history, Georgetown has back-to-back Big East regular-season titles.

DaJuan Summers hit a 3-pointer with 40 seconds to play, and the No. 11 Hoyas celebrated Senior Day today with a 55-52 victory over No. 12 Louisville.

In a tense game between teams tied for first place entering the final day of the regular season, Georgetown (25-4, 15-3) survived Louisville's manic defense and made just enough plays to win. The Cardinals (24-7, 14-4) matched a season high with 14 steals, but they were undone by 4-for-18 shooting from 3-point range and 10-for-18 shooting from the free-throw line.

Freshman Austin Freeman upstaged the seniors by scoring 15 points for the Hoyas, who have won five straight, 12 of 14 and will be the No. 1 seed in next week's conference tournament. Georgetown also has won 22 straight home games.

Terrence Williams scored 14 points for the Cardinals, who were seeking their first Big East regular-season title in their third year in the conference.

The Cardinals, who overcame an 11-point second-half deficit to tie the game several times, will be the No. 2 seed in Big East tournament.

Roy Hibbert had 12 points, six rebounds and four blocks in his final home game for Georgetown. Louisville's big man, David Padgett, had 12 points but failed to grab a rebound.

After Summers' 3-pointer, the Cardinals had three chances to tie. But, just as been the case all day, the 3-pointers weren't falling. Jerry Smith (0-for-6 from 3-point range) missed with 21 seconds to play. After Georgetown's Jeremiah Rivers missed the front end of a one-and-one, Earl Clark's contested 3-pointer was an air ball. Louisville got the rebound, but Edgar Sosa missed a 3 as time expired.

After a first half dominated by defense, both teams discovered some offensive flow in the second half. Freeman scored 10 of Georgetown's 14 points during one stretch with a backdoor layup, a jumper and a pair of 3-pointers as the Hoyas took a 40-29 lead with 14:52 to play.

Louisville countered with a 10-2 run, including two baskets by Padgett — a dunk and a shot over 7-foot-2 Hibbert. The teams punched and counter-punched, with the Cardinals finally tying the game on Derrick Caracter's layup with 6:56 remaining.

It was tight the rest of the way. Padgett picked off a bad pass, and Louisville converted it into a 3-pointer by Williams to take a 51-50 lead with 3:36 left. The game was tied again after Clark made one of two free throws with 1:12 to go, but that would be the Cardinals' last score of the game.

The first half was one long display of riveting basketball between two teams unwilling to give an inch. When Hibbert blocked a shot, Clark immediately did the same thing at the other end. Georgetown and Louisville are two of the top three teams in the country in defensive field-goal percentage, so perhaps it wasn't surprising that the first 16½ minutes featured nearly as many steals (10) as field goals (11).

There was one 5-minute stretch in neither team scored, but it was worth watching because it was defense at its best. Georgetown's Patrick Ewing Jr. alone had two blocks and a steal during the dry spell, but the defensive champion of the half was Smith, who made up for his 0-for-5 shooting with five of the Cardinals' seven steals. The Hoyas led 24-19 at halftime.

The game marked only the second time the Big East regular-season title was decided in a game between two teams tied for first entering the final day. Pittsburgh beat Syracuse 85-84 in 1988.