John McEnroe staged a dramatic comeback Monday to defeat Henri Leconte, 5-7, 7-6 (7-4), 3-6, 7-6 (7-5), 6-1, in the fourth round of the Australian Open at Kooyong.

Third-seeded Mats Wilander, who has won the past two titles here, cruised into the quarterfinals today by defeating Tim Wilkison, 7-6, (7-1) 6-3, 6-3. The match, which was delayed 1 1/4 hours by rain, featured sustained baseline duels

Tim Gullikson withdrew from his fourth-round match with Michiel Schapers of the Netherlands when he suffered severe back spasms toward the end of the first set. Gullikson had won the first set, 7-6 (7-0).

McEnroe rallied from a 2-1 deficit in sets, saved two set points in the third set and was down 1-5 in the fourth-set tie breaker before winning in 3 hours 30 minutes.

"I will always remember today's match when I look back on this crazy life of tennis," said McEnroe, who has beaten Leconte in all seven career meetings.

"At 5-1 in the tie breaker, I was thinking about getting our reservations, and wondered what time the Qantas flight left tomorrow. I was even thinking of getting a wild-card entry to improve my grass court game in the New South Wales championships at White City next week.

"It was a wonderful match, it was one of those great matches. Leconte played great tennis. He's a wonderful competitor, and he's going to finish up in the top 10 for sure."

Said Leconte: "John played brilliant tennis. He is a wonderful competitor, and that's why he is the best grass court player in the world."

McEnroe has failed to win a grand slam event this year. His last major title was in the 1984 U.S. Open singles. He will meet Yugoslav Slobodan Zivojinovic in Wednesday's quarterfinals.

In other fourth-round matches Monday, Zivojinovic defeated Tim Mayotte, 2-6, 6-4, 6-4, 6-4, and Johan Kriek defeated Jay Lapidus of Princeton, N.J., 6-3, 6-4, 6-3.

Television stations pushed back evening newscasts to cover the fourth and fifth sets of the McEnroe-Leconte match, and the press tent was bombarded by phone calls from French television and radio stations when it appeared their 22-year-old champion was on the way to a major upset.

McEnroe played with his left upper thigh bandaged but appeared unhindered. He lost service in the eighth and 12th games of the first set and was in trouble with his service again in the second set.

At one point in the second set, with the score 5-5, McEnroe was talking to spectators, and umpire Richard Kaufman issued a warning.

McEnroe was fined $1,500 after being given a code violation for verbal abuse.