"Is he not the ultimate controller?" she asked reporters at the Television Critics Association Press Tour in Pasadena, Calif., on Sunday (Jan. 13). "Obviously we had to convinced that he had the capabilities of making such a huge change."

"And he's proven that," she added.

"I've been playing tennis a long time, and I've also done commentary for a fair amount of time. I've been looking to do something different than just tennis, because as they say in sports, 'the older you get, the better you used to be,'" McEnroe laughs.

Like ABC's fellow game show "Who Wants to Be a Millionaire," "The Chair" has contestants get in a hot seat -- but in this case one that's hooked up to a heart monitor. As the players answer trivia questions, they must make sure that they keep their heart rate down or else they could lose money instead of winning it.

Unlike on the courts, where he was known for intimidating umpires, McEnroe says his role of the show so far has been to make the contestants feel comfortable -- although that may change as contestants get more savvy about playing the game.

"I prefer to see my role as being more supportive and actually hoping they win." However, he says with a smirk, "yelling is always an option."

But even if the show takes off as hugely as "Millionaire," McEnroe doesn't plan on giving up playing entirely .

"I'm going to cut back significantly if this is successful," he says of spending time on the court. "I've been doing this for 25 years, playing professionally since I was 18. I'm going to turn 43 next month and it would be nice to do something different."

"The Chair" premieres Tuesday, Jan. 15 on ABC.