It seemed a little strange to see Tracy Austin sitting up in the stands and watching tennis.

But there she sat yesterday at the qualifying round in the D.C National Bank Tennis Classic at Rock Creek Stadium, cheering on her boyfriend of a year, Matt Anger.

Her presence certainly did not hurt Anger, a member of the Junior Davis Cup team, as he defeated Claude England, recent winner of the Mid-Atlantic Tennis Championships, 6-1, 7-6.

Anger will have to win one more match today to qualify for the 64-man main draw that begins Monday. The Southern California sophomore will oppose Jeff Papell of Sands Point, N.Y.

"I wouldn't have wanted to be out there today," said Austin, referring to the humidity. Asked if it made her more nervous to watch tennis than to play it, Austin stared intently at Anger serving and said, "Definitely."

Washingtonian Joe Ragland lost, 6-3, 6-2, to Australian Wally Masur. Since he is ranked 102d in the world, Masur would not have had to qualify if he had registered in time.

Masur defeated another native of Washington, Mark Williams, in the second round, 6-3, 6-2. It was a tough defeat for Williams, a 23-year-old pro whose 6-5 stature is better suited to a faster surface than the Rock Creek clay.

"I have to work to support myself and I just don't play as much as I would like to," said Williams, who works for a telemarketing firm in Rockville. "It's especially tough for black players to get the funds to play each week.

"Take Joe, for example," Williams said, pointing to Ragland, another pro. "He defeated Tom Cain (a high-ranked pro) in the Middle Atlantic two weeks ago but then he couldn't go to Boston last week like Cain did. Cain won a couple matches there before he lost to (Guillermo) Vilas."

Williams, who attended Howard, was upset over the fact that he, Gebre Wallace of Oceanside, Calif., who is also black, and Ragland were all put in the same part of the draw. Only one of them could have qualified for the main draw. Six blacks, in all, played in the 42-man qualifying field.

Tournament officials said that the selection is done by numbered chips and is totally a matter of chance. Purcell Puts Out Lendl

BROOKLINE, Mass., July 17 (AP)--Mel Purcell, dashing from side to side despite the heat and humidity, stunned Ivan Lendl, 2-6, 6-3, 6-2, today to move into the semifinals of the $200,000 U.S. Pro Tennis Championships.

Both players suffered from the temperatures that climbed to well over 100 degrees on court, but Lendl, seeded second, suffered more.

"Both of us were as tired as can be," said the seventh-seeded Purcell, of Murray, Ky. "When he gets tired, he gets impatient and doesn't rally with you as much . . . I think the weather was definitely to my advantage."

Purcell, who will play in Sunday's semifinal on his 23rd birthday, will face 12th-seeded Fernando Luna. In a 2-hour, 38-minute match today, Luna beat 13th-seeded Alejandro Ganzabal, 7-6 (7-2), 4-6, 6-3.

Lendl, who is the No. 1 seed in next week's D.C. National Bank Tennis Classic, broke Purcell's serve in the fourth game to tie the third set at 2-2. But the clay-court specialist with the big forehand had nothing left after that.

Lendl, who has won eight tournaments this year, got just two points in the final four games. Heidenberger Beaten

RICHMOND, July 17 (AP)--Top-seeded Kathleen Cummings of Richmond defeated defending-champion Betsy Heidenberger of Chevy Chase, Md., 6-3, 6-3, today to win the singles title in the Mid-Atlantic women's tournament.

Heidenberger, a recent North Carolina graduate who was seeded second, broke Cummings twice in the first set, but Cummings came back with three breaks of her own.