They are still there, huffing and puffing, arms-crossed with their bottom lips sticking out. They didn't show up for the post-event press conference to talk about Haiti, and they still haven't emerged.
How is it possible that neither of these guys has had the decency to offer an apology yet?
We saw on Friday at the Hit for Haiti how small both of them really are, but these two sports giants have only managed to continue shrinking since.
"Now being a father,'' Roger Federer said Sunday night, "I thought maybe we'd have to give both guys like a timeout or something.''
I called for a spanking.
This was a study in rivalry. But it comes off like a Seinfeld episode, when a charity event turns ugly through self-obsession.
For some reason, people seem to want to focus on which one was more wrong Friday night. Well, the he-started-it argument works fine in second grade, but for grownups, it doesn't matter.
Sampras is not excused from hitting a serve at Agassi's head just because Agassi was a jerk first.
How much was Sampras supposed to take? He should have taken as much as Agassi dished out.
If he wanted to respond, maybe the locker room afterward would have been a better place. But not in front of 16,000 people who came to the stadium in Indian Wells to see eight tennis legends, past and present, help a country in disaster from an earthquake.
The entire tennis community had a stake in this. Tennis fans are all in one club together, a fraternity of sorts.
That club has been known to be led by snooty, self-absorbed, ego-driven, entitled athletes. This moment not only would have helped others, but also would have been a sign that tennis has a heart.
Throughout the years, Agassi was the loud one, with ups and down, flash and fire.
Sampras was quiet, robotic, classy. Sampras was unflappable and Agassi was flapping all over the place, a career of extremes.
It's easy to choose sides, based on your style. And that's what people are doing about the Hit for Haiti, as if this is a simple black hat-white hat thing, like the rivalry.
It took Agassi this long to pull Sampras into the gutter with him. When they faced each other in their primes, Sampras won so much more than Agassi. But Agassi still got all the attention.
Surely, each one wanted what the other had. But Sampras always flew above Agassi as a player and as a class act. Now, Agassi finally made Sampras look bad.
Agassi remains such a curiosity. He started as a young punk and seemed to grow up so well. He started a school for disadvantaged kids, and did wonderful things straight from his heart.
Still, you always wondered if he was -- is -- a fake. His kindness always came with melodrama. I figured the effort he put into that school was far more than any phony would be willing to do.
Then, last year he helped to write a book about his life, admitting to using crystal meth regularly as a player. He said he told his story to help others, but if his heart was calling for him to help, then why did it take a six-figure book deal to do it?
It's impossible to tell what his soul is about. Is he a fraud? Can he be good-hearted and mean-spirited at the same time? I can't tell if his bitterness Friday showed what he's all about, or if it just showed how he feels about Sampras.
After Sampras left, Agassi went to the valet to find out how much of a tip Sampras had left. The answer: One buck.
In the past few weeks, Sampras said he and Agassi needed to talk man-to-man.
Agassi had gotten to him.
On Friday night, Agassi and Rafael Nadal played doubles against Sampras and Federer. All players wore microphones.
Agassi, true to his personality, decided to make a running commentary throughout the night. Sampras, true to his personality, barely said a thing.
At one point, Agassi made fun of Sampras for being too serious.
"OK Andre, I'll joke around a little bit,'' Sampras said. "I'm going to imitate you.''
Then Sampras stood pigeon-toed and started waddling, a perfect imitation of Agassi.
For some reason, Agassi was furious.
"I want to impersonate you,'' Agassi said.
Then he pulled out his pockets and said, "I don't have any money. I just like. . .I. . ."
"Oh,'' Sampras said. "About my tipping? OK.''
"No,'' Agassi said. "No wait. I've got a dollar.''
Sampras: "That's how you want to play, huh?''
Agassi: "Oh, it's all fun and games till somebody gets hurt.''
Then Sampras hit a serve at Agassi's head.
Federer, who would call it an awkward and heated moment, said he didn't know what to do, that he couldn't say anything to Sampras, his partner, because he had the mic on, too.
But it was an important admission that Federer made, that this was a serious moment. Tournament owner Larry Ellison tried to pass it off as part of a show.
It was not.
Nadal said that Sampras and Agassi spoke English too fast for him: "I was very happy I didn't understand nothing.''
Also not true.
"You know what,'' Agassi said during the spat. "It's better than being a valet driver when you pull up.''
"Let's talk about our 'baggage,' '' Sampras said, rolling his eyes and referring to Agassi's book. "There we go. I'm a bad tipper. I'm sorry Barack Obama."
Sampras was better in quiet strength. He complained that Agassi had gotten "personal.'' But Agassi's baggage was very personal to him, too.
In the end, neither one could be the bigger man. They're still shrinking.
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