John McEnroe says he is going to...

John McEnroe says he is going to quit tennis permanently if he doesn’t regain the form that once had him ranked No. 1 in the world.

McEnroe, 29, demonstrated flashes of his old form last week in reaching the title match of the $415,000 U.S. Hardcourt Tennis Championships at Indianapolis. Sunday, he lost to top-seeded Boris Becker, 6-4, 6-2.

“I’m just not consistent on my passing shots,” said McEnroe, who was the world’s top-ranked player from 1981-84 and is currently No. 17. “My concentration is nowhere near what it was a few years ago. When you’ve done a lot of things, you’re not as hungry as you were, so you have to look for other ways to be hungry.”

McEnroe took six months off in 1986 after marrying actress Tatum O’Neal. The couple, now with two young sons, celebrated their second anniversary earlier this month.

McEnroe hasn’t set a time limit for his climb back to the top, but he vows to retire if he proves unsuccessful.

“There’s no doubt in my mind that if I continue to play like this a year from now, I don’t know how much longer I’d be playing,” he said. “The next couple of months, especially October and November, is my opportunity to get back in the top 10.”

In another tennis development, Becker, two-time Wimbledon champion, withdrew from the $815,000 Player’s International tournament with injuries to both feet that could keep him out of the U.S. Open.

A physician described the injury as an inflammation of a fibrous tissue that runs from the heel to the toe. Becker is said to have a 50-50 chance of healing in time for the Open Aug. 29-Sept. 11.