While the rest of the Notre Dame players were in with Coach Digger Phelps watching films and preparing for Saturday's 8 o'clock game with Maryland, Tom Sluby talked with a visitor about learning a terribly painful lesson he calls "the best thing that ever happend to me."

Sluby, a sophomore guard from Gonzaga High School and Notre Dame's third-leading scorer, learned 11 days ago that his basketball season was over. Sluby's 1.8 grade point average--three Cs and one D--for the fall semester made him ineligible to play basketball until next year.

"In the long run," Sluby said, "this lesson is going to make me a more responsible person. I didn't find out about being put on probation until my grades had arrived at home in Washington, and I called home to hear what they were.

"Right away, I became depressed. I kept thinking, 'How could I let this happen?' I think I'm pretty intelligent. My freshman year, I did well academically. But this past fall, I know for sure that I didn't apply myself. I didn't work up to my potential. It won't happen, ever again."

Sluby, The Washington Post high school basketball player of the year in 1980, did not flunk out of school, flunk off the team or even flunk a class, as many people here and back East believe. Nor is he planning to transfer to another school. According to NCAA rules, in fact, Sluby still is eligible for competition because his cumulative grade point average is higher than 2.0 (2.13 after the fall semester).

But the Notre Dame athletic department says its student-athletes must maintain a 2.0 index every semester to be eligible. "That rule we have here is a very good rule," Sluby said.

Sluby, who is enrolled in the College of Business Administration, got C's in Economics, Accounting and Anthropology and a D in a marketing class.

"I wanted to do some extra work in my marketing class and get the grade changed," Sluby said. "But the professor said no. He wouldn't have done it for any other student, so why should he do it for me because I'm a basketball player? That was 100 percent fair. You can't expect to go through life asking for things.

"Looking back on the semester, I know what happened. I just did assignments to get them done, just to turn it in on time. I wasn't doing the work for the sake of learning, and that can cause problems around final exam time.

"But I've learned not to assume, 'Well, I'll get over easy this time.' I've also learned not to procrastinate, to go right at my assignments. From now on, I'll learn for the sake of learning and not to satisfy the instructor by going through the motions.

"Digger said I should get a 2.8 this semester," Sluby said. "But my goal is to have a 3.4 (on a 4.0 scale)," which would be an A-minus.

This semester Sluby is taking a full load of classes; he has a statistics class that is said to be the hardest course in the business school. Sluby also has economic geography, economic principles, informal logic and business management theory--not the typical course load of a college athlete.

Sluby is intelligent, articulate and witty. He made second honors at Gonzaga as a senior. His favorite class that year was physics, a course generally approached with fear and loathing by even the best of students. "I feel I can get As and Bs in any courses offered here, if I apply myself," Sluby said.

"Tommy doesn't load up with patsy classes," said Dick Myers, Sluby's coach and English teacher at Gonzaga. "It was a shock when I heard the news of Tommy's ineligibility. But I can understand how it happens. It's certainly no indication of his intelligence, though."

Sluby is perturbed to be in this situation. He was improving rapidly as a basketball player, but now will miss the last 14 games.

"It's the best thing that's ever happened to him," Phelps said. "He would be eligible at a lot of other schools, maybe developing a bad habit of just sliding by. This hurts him now. But he's got to be a man and grow through it . . . straighten his priorities. You know, he's even played better in practice since then."

So for now, Sluby practices with the team when necessary or convenient, and works toward his goal of a 3.4 average.

"Learning is going to be fun again," Sluby said. "There's not a lot of hanging out you can do here in South Bend. It's not like I can head out for Georgetown every night. I got myself into a mess, a serious mess. So I'm just going to get on top of my books and stay there. I'm just a regular student this time around."