By Steve Ginsburg
(Reuters) - Tennis legend John McEnroe faces James Blake on Wednesday in a match in which they will call their own lines - declaring whether the ball is in or out - a wrinkle that McEnroe knows may draw more than casual interest from fans and former linesmen.
During a career in which he won seven grand slam singles titles, McEnroe was known as a sometimes volatile player who periodically berated linesmen over what he saw as blown calls. "You cannot be serious," he once yelled in a famous tirade over a line call.
"I'm sure there will be some umpires out there that will be saying, 'See, it wasn't as easy as you thought it was,'" McEnroe, 56, told Reuters. "It's undoubtedly true."
He added, "Who would want a job where the only way you get recognized is if you made a mistake?"
McEnroe will take on Blake, 35, once ranked fourth in the world, as part of the PowerShares Series for former champions over age 30. Andy Roddick faces Jim Courier in the other match in Lincoln, Nebraska, with the winners meeting for the title. The matches are just one set.
There are unlimited challenges, to be decided by the Hawk-Eye computer used on the pro tour, but McEnroe insists no player wants to make a bad call against his opponent. The last time McEnroe called his own lines in a match was as a junior player.
"I would be mortified if someone accused me of cheating," McEnroe said. "I often played balls that I'm pretty damn sure were three, four, six inches out because I didn't want the guy to call me a cheater."
Thursday's event is the third on the 12-city PowerShares series tour. McEnroe did not play the opening two events.
"It makes for an awkward moment when someone calls a ball and you challenge them," said Roddick, 32, who won last Wednesday's stop in Los Angeles.
"You run the risk of calling them out before thousands of people. But knowing John, he'll be pretty upset with any way that it turns out," Roddick added with a chuckle.
McEnroe said he feels a mixture of nerves and excitement.
"It's bad enough when you're losing to someone but then if you feel he was making a bad call, it becomes more personal," McEnroe said. "If you challenge them, at least you'll be able to expose them for deliberately making a bad call. I doubt they'd do it again."
(Reporting by Steve Ginsburg in Washington; editing by Will Dunham)