John Whitlinger has been down so long, the quarterfinals of the $100,000 Volvo Classic really look like up to him.

Six weeks ago, the 1974 NCAA singles and doubles champion from Neenah, Wis., was ready to give the ghost of a two-year pro career the quit tennis.

His most reliable strokes were failing him. He was stale, lacking spark on the court. He knew it was time to split from his coach of 14 years, but the decision was painful because the man is his father.

Whitlinger felt a bit like a skid row bum in a moment of introspection. "I thought about some of the other players who have won the NCAA Jimmy Connors, Dick Stockton, Stan Smith, Arthur Ashe, Bob Lutz, et al). About where they are and where I am. I felt like a failure at 23."

Tonight, Whitlinger plays Lutz at George Washington University's Smith Center, his first appearance in the quarters of a tournament since the Japan Open in November.

He already has earned $2,900 here, and a victory over Lutz could guarantee an additional $2,300. This is found money, not to mention peace of mind, for Whitlinger, who lost in a qualifying match last weekend but got into the draw as the last of three "lucky losers" when his former Stanford teammate, Roscoe Tanner, withdrew because of bronchitis.

"I had been used to winning all through the Juniors and college, but all of a sudden I couldn't win to save my life. My game was going to pieces. It was frying my mind," Whitlinger said yesterday after beating 1976 Australian Open champion Mark Edmondson, 6-2, 3-6, 7-5.

The match was tense, fiercely fought, but whitlinger stayed loose. When he sailed a backhand 20 feet long late in the tight third set, he held up his racket as if it were a fishing pole and mimicked reeling the shot back in.

"I've changed my attitude within the last two weeks," he said. "I'm playing one point at a time. If I mishit one, I figure there's another point, a new opportunity.

"I was ready to pack it in on Feb. 4, my birthday. I'll never forget that day. I lost to Trey Waltke at a tournament in Dayton, played just awful, and we had a big family rap session to decide which way I should go."

He had always been coached by his father, Warren, a 5-foot-7 basketball all-America at Ohio State in 1936 who did not play tennis but immersed himself in the sport after his son showed an early interest in it.

"He had brought me through the Juniors. We won every big Junior title except the National 18s. We won the NCAAs. But all of a sudden we stopped relating as a coach-player. Not as father-son, but the coach-pupil relationship just wasn't there anymore," Whitlinger said.

"So we had a big family pow-wow. My father was there, my mother, my sister and brother-in-law, and may niece, who's 2 1/2 months old feel asleep. It went on for 3 1/2 hours. We're a very close family, and it's good that we can let things fly.

"I told my father things that night I had never said to him before. But everybody was behind me 100 per cent. We decided I should go to someone else I could relate to better. Still, I made a point of saying, 'Dad, if I ever need you, I'll know you're there.'"

Two weeks ago, Whitlinger went to Dave Saxe, a teaching pro in Milwaukee who has watched him play for eight years. They spent seven days together, "getting up at 6 a.m. to hit a thousand tennis balls before breakfast," correcting flaws that had developed in Whitlinger's technique and mental approach to the game.

The bulk of the technical work was on his two-fisted backhand, the foundation of a game that is built around return of serve, passing shots and quickness.

"He told me to hit the ball closer to my body, not so far out in front," Whitlinger recalled. "It was just a little thing, a few words, but I started executing better. And that straightened out my mind.

"Now I'm playing much better, hustling, enjoying the game again. Before, I was lying down on the court and dying, something I'd never done before. Now I'm using my speed and running down shots. My game's not to where I want it, but its going in the right direction."