When second-place Georgetown takes the court against seventh-place Seton Hall Thursday night (7 p.m. WTTG-TV-5) in its Big East Tournament opening-round game here, the Hoyas will be facing a team they defeated twice, but by a total of just three points.

Many people here, including Dave Gavitt, commissioner of the Big East, think Georgetown is the favorite to win the tournament. If the Hoyas do successfully defend their conference title, they probably would move on to the NCAA championships (the conference winner does not receive an automatic bid).

But before thoughts turn to national titles, this conference, the most balanced in the nation, will entertain nearly 25,000 in the Carrier Dome and decide who is the best in the East.

In the afternoon doubleheader, regular-season champ Boston College (21-5, 10-4 in the conference) will play last-place Providence (9-17, 8-6) will play Connecticut (19-7, 8-6). In the evening, Host Syracuse (15-11, 6-8)) will face St. John's (17-9, 8-6) immediatley after the Gu-sEton Hall match.

The GU backers point to the Hoyas' depth, late-season resurgence and experience; the Hoyas advanced to the NCAA's regional final last year. They also point out that Georgetown won seven of 10 games decided by two points or less this season, while Seton Hall has lost six conference games by a total of 11 points.

But the Pirates (11-15, 4-10 in the conference) have been tough for the Hoyas. Only Fred Brown's rebound bank shot at the buzzer in overtime enabled the Hoyas to escape Seton Hall's home court with a 52-51 victory early in the season. And GU barely held on for a 58-56 triumph at McDonough Arena.

"I don't know what it is between these two schools," Seton Hall Coach Bill Raferty said. "It's a crazy thing the way these games are decided at the end. "One kid will come up with a big play for either team. We're excited about it. Very excited."

Seton Hall outrebounded the Hoyas in both games and held a decided edge in the front court with Sir John Collins and Howard McNeil. The tempestuous Raferty intimidates officials better than anyone in the league. And the throng in the Dome is likely to expend as much energy jeering the Hoyas, as cheering host Syracuse.

"Seton Hall can be as good a team as there is in this tournament," said Boston College Coach Tom Davis, the conference coach of the year. "But whether they can sustain that intensity for three games (to win the championship) is doubtful."

The Pirates only have to sustain it for the better part of 40 minutes to spoil an excellent end-of-the-season GU rush in which the Hoyas hve won eight of their last 10 games. The two losses came on the road against regular-season champion BC and here, a controversial defeat.

Georgetown's experience, and its back court of Eric Floyd, Fred Brown, and Gene Smith -- which Davis calls the best in the conference -- should be enough to wring out another close victory and advance the Hoyas (19-10, 9-5) to the semifinal round against the St. John's-Syracuse winner.

Since the games against the Pirates, Hoya relief center Mike Frazier has played the best basketball of his career. He played only 26 of 80 minutes against Seton Hall in the regular season, but the fact that the 7-footer made five of six field goals for the smaller Pirates will not be lost on Thompson.

Seton Hall's high-powered back court of Dan Callandrillo, the league's third leading scorer at 17 points per game, and Matt Piccinich will be shadowed from the start by the quicker Gene Smith, whose role since becoming a starter in Thompson's lineup has been defense.

Georgetown followed Seton Hall onto the practice floor today, the hour and-a-half sessons open to reporters for the only time during the tournament.

When Raferty lost track of the time and a GU official had to remind him it was the Hoyas' turn, Raferty replied with mock fear, "Hey boys, let's go. iYou know. . . Georgetown. . . John Thompson. He'll beat the crap out of us.Let's be nice to them. Remember tomorrow."

Once on the floor, the Hoyas practiced poorly, Thompson said. "Practice was awful," he said. "I hope they're overeager." But the coach said that his team is not accustomed to practicing amid the distractions that were present in the Dome. Thompson too, sees a two or three-point game Thursday.

"I can't even remember the last time I've been able to sit back and watch a game relaxed. They're all close."

For those who insist that Georgetown is the favorite to win the tournament, Thompsn had these word: "All those people, please tell that to the NCAA selection committee, so they'll have that already in their minds when they pick the 48."