Andre Agassi is only one of countless people who have witnessed Tony Bennett's a capella rendition of "Fly Me to the Moon."
"I'm telling you, Tony Bennett walking to the front of the stage without a microphone, singing a capella in Carnegie Hall ... you have seen it all when you've seen that," he says.
But context counts. Agassi heard this performance on Sept. 27, when he was one of four recipients of Bill Clinton's first Global Citizen Awards. And the retired tennis great should hear Bennett sing again Saturday, at Agassi's 12th annual Grand Slam for Children concert.
The benefit raises big money -- $8.6 million last year -- for Agassi's foundation and charter school, the Andre Agassi College Preparatory Academy.
Clinton also singles out the foundation in his new book, "Giving." The 37-year-old Agassi says he appreciates Clinton's award as one that recognizes the event as something that can be modeled. "It's one thing just to help kids, another thing to help them in a way that can be duplicated."
This year's Grand Slam is the first in which all preparations fell within Agassi's post-tennis life; last year's event fell only a month after a dramatic farewell speech and thundering ovation at the U.S. Open. "I can share some of the burden like I couldn't do the last 11 years. I think I'm more relaxed as a result of that," he says.
Saturday's concert at the MGM Grand Garden continues to give both the city's richest corporate players (who come early for a banquet and auction) and the average Joe a concert lineup that turns heads even in a city routinely packed with star power. Earlier this week, $96 tickets were hard to find in pairs, but $56 and $76 tickets were still in supply.
(The public also is invited to watch, from a distance, red carpet arrivals on the east side of the arena at 6 p.m.)
As always, many of this year's stars are participating in the concert based on personal connections with Agassi.
• Tony Bennett: "Our roads have crossed on a number of occasions before," Agassi says. Bennett is an avid tennis enthusiast who takes lessons from veteran Las Vegas pro Marty Hennessy.
"Tony has been a friend of my dad (Mike) a long time. ... When I saw him (at the Clinton event), he asked how my dad's shoulder is doing, because he had surgery a number of weeks ago."
• Kelly Clarkson: "Kelly Clarkson gets me through many 50-minute runs in the desert on my iPod," Agassi says of the "American Idol" pop queen. "She transcends a few generations. My kids love her, so we just reached out, hoping she would come share some of her talent. I just think she's a doll and a half."
• Jerry Seinfeld: "He called me to do the show this year. We've been trying to get him for a lot of years, so I called him back as soon as I got the message.
"He said, 'I never really understood what it is you do and what it is you care about and how it is you care about it until I saw you at the Open this year. When I saw you at the Open, I finally felt like I understood you. If you want me next year for your event, I'm in.' "
• Matchbox Twenty: "Rob (Thomas) was going to do the event a couple of times. Last year he was in South Africa. We had some logistic issues for a couple years. So he asked if I could reach out to him earlier: 'Can you let me know so I can schedule it earlier?'
"I said, 'Well I'm lettin' you know. What about next year?'
"He was like, 'Count me in.' "
This year's show also includes Flamingo headliner George Wallace and guitar great Carlos Santana, who also performed at the 2002 benefit. Having Santana and Thomas on the same bill raises expectations for a performance of "Smooth," the 1999 hit from Santana's "Supernatural" duets album.
In the past, Agassi says the concert was slotted during the only break he could take in his tournament schedule. "I always felt like it came with a cost. I was compromising my preparation," he says.
Now, "it was well worth the cost," he says. "While I was playing tennis, I was building this foundation that I knew one day would take over most of my life, and it has.
"My hope is that my next 21 years sort of outshine my last 21 years," he says. "I feel like I have an empty canvas now to do whatever it is I value and care about."
For the first time this year, the top donors who buy the $40,000 and $85,000 tables for Saturday's show will be treated to a second concert: Seal and John Oates performing an acoustic concert today at the Springs Preserve.
For shelling out "a ridiculous amount to pay for an evening," Agassi says, "we figured we'd give them a casual evening on Friday night too."