The ball was clearly out . . .

The Associated Press files a report today on the use of instant replay in professional tennis. Some players like it -- Andy Roddick and James Blake, notably -- and some don't -- count Roger Federer in this camp.

Here's Roddick on the system: "I think it's great what they've done with the challenge system," Roddick said. "I think it takes a lot of the question out of it."

Blake: "It humbles the players sometimes. It humbles the officials sometimes. And I think it's great because we're probably both too arrogant at times. The players always think they're right and the umpires always think they're right, and it shows that neither of us are always right."

And here's Federer, arguably the greatest to ever play the game, on challenges: "I think it's nonsense," he said. "Now they can hide even more behind these calls. We would like to be able to rely a little bit on umpires. They tend to now just let us do the work, the tough stuff. They let us get embarrassed, basically."

Personally, I'm all for the instant replay system -- which gives players two challenges per set -- with one caveat. I don't think it should be used in a tournament unless it is available on every court. Otherwise, matches are being played under different conditions, which, I think, erodes the credibility of the tournament.

Still, I think Blake sums it up best: "As long as the fans like it," Blake said, "I say we keep it."

Serena living large Down Under

Anyone who has watched the Australian Open these past two weeks has to be surprised by two things -- the size of Serena Williams and the incredible run she's on (she'll play Maria Sharapova in the final tomorrow). To the critics of Williams' seeming out-of-shape-ness (yeah, I know, that was awful grammar) and lack of competition, Peter Bodo says shut up and enjoy watching a champion work.

So it's about time that critics stopped whining about the quality of the competition, or the way the other women shatter like dropped crockery the minute Serena fixates on them with that disconcerting, hard stare. This isn't about the shortcomings of WTA pros. It's about the strength and will of Serena Williams. This clearly is a woman with a big appetite that isn't satisfied by mere food.

Keep in mind that Williams played in all of four tournaments last year while dealing with injuries. Her last tournament of the year was the US Open, where she lost in the fourth round.

After roughly four months off, to make a Grand Slam her second tournament back -- and to make it to the final to boot -- is just amazing. For a long time I was not a fan of Williams. The level of play and the drive to win that she has exhibited in the last two weeks has changed my mind.

For a preview of the final from ESPN analyst Mary Carillo, click here.