LOS ANGELES -- It takes a lot to upstage The Queen Of Pop.

But even the executive producer of the Grammys admits Madonna's opening number of Music at tonight's ceremony (8 p.m.) will likely take a back seat to the controversial closing duet by pottymouth rapper Eminem and gay rights supporter Elton John.

"We've never had this kind of controversy," says Canadian-born Pierre Cossette, who's been at the helm of the Grammys for the last three decades. "A lot of people are going to tune into this. The people that think it's a bad idea are going to tune in, and people that simply want to know what the hell the fuss is about will too. Because 80% of the people have never heard this music, they've just read about it. So they'll be very, very inquisitive."

Quadruple nominee Eminem will close the three-hour Grammy show with Stan, his song about a deranged fan. John, on piano, will sub for original collaborator, British female singer Dido.

"We got a call from Elton John, who thought he'd like to work with Eminem," explains Cossette, a native of Valleyfield, Que. "This is out of respect for their mutual talents and contributions and accomplishments, because they're on opposite sides of the world, culturally."

Because of Eminem's perceived homophobic and misogynistic lyrics, the duet has irked gay, women's and religious groups, who plan to protest outside the Staples Center.

Even Canadian Grammy nominee Ed Robertson of the Barenaked Ladies, whose single Pinch Me is up for best pop performance by a group, is incensed.

"Wow, Sir Elton! Eminem is going to call him a 'f---in' faggot' and kick him, and walk off the stage -- it's going to be great," says Robertson sarcastically. "I think that's messed up completely. I think Eminem is an amazing writer and an absolutely gifted rapper; he's just not a very good human being. He's not very socially aware. He's an angry person who has misdirected his anger at all the wrong places, I think, and unfortunately, he's influencing a huge group of confused teenagers to do the same."

In another strange twist, the seating arrangements for the audience at the Staples Center have George Michael, another openly gay performer, seated directly behind Eminem. Eminem has also just been confirmed to perform at the Brit Awards next Monday, with gay activists preparing to demonstrate there as well.

"As a parent I don't want my kids to hear it," admits Cossette of Eminem's highly charged lyrics. "I mean, what kind of a thrill can you get about stabbing your girlfriend and having sex with your mother and all that kind of stuff? My kids are grown, but I have grandkids. They're six and eight, that's pretty young, but I guess they are impressionable. The adults -- and I certainly don't blame any of these organizations that are marching on the show -- 99% of them have never listened to the record, they just know the guy, his subject matter is taboo."

But even Madonna, who will reportedly appear at the beginning of the show on a rhinestone-studded horse being pulled by teenaged rapper Lil' Bow Wow, has joined the pro-Eminem ranks.

In a letter to the L.A. Times, which she signed Mrs. Ritchie, Madonna says Eminem's language is less offensive than that of the current American president.

"What is the big problem about Eminem?" she writes. "Since when is offensive language a reason for being unpopular? I find the language of George W. Bush much more offensive. I like the fact that Eminem is brash and angry and politically incorrect. At least he has an opinion. He's stirring things up. He's provoking a discussion. He's making people's blood boil. He's reflecting what's going on in society now. That is what art is supposed to do."

Eminem, John and Madonna are just three of the high- profile artists gracing the stage at the Staples Center. Other performance highlights should be provided by U2, Sheryl Crow and Shelby Lynne, Dolly Parton and Brad Paisley, Macy Gray, and Moby with soul newcomer Jill Scott and performance artists Blue Man Group. Canadian content will come via Montreal-born classical pianist Marc-Andre Hamelin, who is performing, and presenters Joni Mitchell, a double nominee, and Robbie Robertson.

This year's telecast has definitely been a strange one in terms of last-minute decisions. For example, just two days ago Paul Simon and Lil' Bow Wow were added to the performing lineup. And less than a week ago, sardonic comic Jon Stewart was finally announced as host.

"Whoopi Goldberg, she got sick, she had to go to the hospital," explains Cossette of the original Grammy host. "She had a kind of a heart problem. The doctors had to reduce her workload 'cause she was working so many shows and, of course, Whoopi was very disappointed. So, anyway, that problem is solved and we're very happy with (Jon Stewart)."