Georgetown and Virginia, who almost cracked the top-10 rankings earlier this season but are not struggling, meet tonight in the first round of the National Invitation Tournament.

Georgetown, 21-6 after two straight losses, will be playing without senior guard Derrick Jackson, who is recovering from a bleeding ulcer. Coach John Thompson said Craig Esherick, who launched the "miracle" shot against George Washington, will replace the Hoyas' all-time leading scorer for the 8 p.m. tipoff at University Hall.

The game will be broadcast by radio station WEAM-1390.

In the Cavaliers' camp there is doubt about the availability of freshman guard Jeff Lamp and sophomore forward Mike Owens, who have lingering ankle problems. "It gets to the point where you get diminishing returns," said Coach Terry Holland.

Virginia has been struggling for better offense the last few weeks and Lamp, the Cavaliers' leading scorer, said he doubts he will start or play more than 10 to 15 minutes tonight. He said he is not satisfied with his game and that it has been affected by the injury.

The Cavaliers, once as high as 11th nationally, have split their last 10 games. They are 20-7 and fell out of both wire-service polls this week. Georgetown which had ranked as high as 12th during a 13-game winning streak, remained ranked only by UPI's coaches this week, in 20th place.

Jackson remained in Sibley Hospital in Washington last night. He is scheduled to drive here today with Dr. Carl McCartee, Georgetown's team physician. It has not been decided whether Jackson will dress for the game.

Thompson received a scare in yesterday's closed practive when starting forward Steve Martin collided with teammate Felix Yeoman and struck his head on the floor. Martin did not resume practice, but did not appear to be hurt.

Once it became apparent Jackson would not be ready to start tonight, Thompson considered two alternatives in order to continue to use 5-8 guard Mike Riley in relief.

He could start Esherick or shuffle the lineup considerably by moving Martin to point guard, John Duren from that position to Jackson's slot and A1 Dutch to forward.

Before practive, Thompson said he had decided on Esherick, whose 35-foot shot sent the GW game into overtime and allowed the Hoyas to eventually win.

"He's a senior and he may want it more," Thompson said. "He's Derrick's roommate and he's worked hard all year. He deserves it.

"He has all the reasons in the world for wanting to do it. Plus we need a shooter. I've got to see early if he can stick it in the basket. I expect Virginia to play a lot of zone."

Esherick, a Springbrook High School product, played 176 minutes in 17 games this year. Although regarded as a strong outside shooter, Esherick made only 40 percent of 90 shots this season.

Thompson said Martin also will play point guard. Thompson plans to use his reserves often because the Hoyas want a fast-paced game, and they must press to do that against a Virginia team that likes a slow tempo.

Riley insists that Jackson's absence affected the Hoyas more mentally than physically in their last game, the 88-75 ECAC playoff loss to Virginia Commonwealth. Nevertheless, without Jackson, who has an 18-point scoring average, Georgetown will be without one of its three regular scoring threats.

That's why Thompson needs a hot-shooting Esherick. "Everybody has to play well," Thompson added.

Virginia shot so poorly in its last two games (39 percent against Maryland, 40 percent against Wake Forest) that Holland said:

"The law of average has to catch up with us. We'll probably make them all (their shots) the way we've been going. You have to keep taking good shots and the ball will go in eventually, both individually and as a team."

The tendinitis in Lamp's right ankle has bothered him so much because of the constant pounding since mid-season that he has altered his shooting style and is taking only half as many shots as he did earlier.

"The ankle has cut down my mobility," he said. "I have trouble getting off the ground as much as I used to. Because of that, you start changing your shot subconsciously. It throws off the rhythm of your shot."

As a result, Lamp said, he is not passing up his shots when he gets them but is not working as hard to get open either. "I was taking 15 to 20 shots early in the season. Now I'm taking eight, nine or 10," he said.

"I'd like to show people I'm a better player than I've been playing."

Yet, Holland is satisfied with his freshman's statistics - a 17.6 scoring average and 41.2 percent marksmanship that the coach says is deceptive because teams take fouls that deprive him of easy shots. Also, opponents are zoning the Cavs so much that Lamp is not able to get inside and use his foul-drawing, double-pump moves.

Holland insists that Lamp draws fouls so well the referees eventually stop called them. Lamp is an 84.8 percent marksman at the foul line, with 197 attempts.

"He's had a great season," Holland said. "How much more can the poor guy do? He gets very few easy baskets. The book on him is to beat the heck out of him and see if he can take it. It'll balance out by his senior year, if he's still alive.

"Ford (North Carolina star Phil Ford) is an example of that. He gets a few breaks now. Everybody's a fan of his - me, the officials. Every player who's reached that stature gets those breaks."

Holland said that both Lamp and Owens definitely will play. If Lamp doesn't start, Dave Koesters will be at his position. If Owens doesn't start, slumping Steve Castellan will.

The winner of tonight's game advances to the quarterfinals against either Dayton or Fairfield, who play Saturday night at Dayton.

Without a large gym for a home game, Georgetown is "one of our traveling teams" under the NIT's new money-making regional format.

Nevertheless, Holland had words of encouragement for Thompson.

"Look at it this way, John," Holland said. "You played Virginia Tech at Blacksburg last year. You're playing a little bit closer to New York this year. You have to admit Charlottesville is a little bit better than Blacksburg."