It was the power pop summit nobody thought would ever happen again. Madonna was set to reunite exes Britney Spears and Justin Timberlake onstage Thursday night during a stop on her Sticky & Sweet Tour at Dodger Stadium in Los Angeles. Only Madonna, who had worked with both singers in the past, could bring the former Mouseketeers and teenage sweethearts back into the same frame.

Well, there are some things even Madonna can't, or won't, do. Though Spears and Timberlake both hit the stage with Madonna at the show — which was delayed three hours due to problems with the set — they did it at separate times, according to E! Online. Britney, wearing black pants, a white tuxedo-style shirt and black heels, came out to join Madonna for the show's third song, "Human Nature."

(Check out photos of Britney's performance with Madonna here.)

One fan told OK! magazine that it was a whole new Spears who performed with her former VMA smooching partner. "This was a completely different Britney from a year ago," the unidentified concertgoer told the magazine. "She was glowing! It looked like she actually wanted to be on the stage."

While there were no kisses this time, the pop divas apparently bonded onstage, as Madonna flung her arm around Britney's shoulder as soon as the singer came out and told the crowd, "She is not your bitch," prompting Britney to laugh and drop her signature line, "It's Britney, bitch." The two did actually kiss as Britney left the stage, but only on the hand.

According to reports, due to a collapse of some of the stage on Wednesday, it was unclear if the show would go on at all, but Madonna said she was determined to pull it off, even if it meant using mood lighting.

"Half of my stage is missing ... which is why we're in the dark," Madonna told the crowd, according to E!. "The absence of light makes it very hard to look into the audience eyes, and that's what makes performing such a joy. So come close. And thank you for your understanding."

While Britney enjoyed her moment in the spotlight (her first major live performance since the disastrous 2007 VMAs), the singer was quick to leave the backstage area moments after Timberlake re-upped with Madonna for their Hard Candy duet, "4 Minutes," later in the show. It's unclear if Spears and Timberlake had any face time backstage.

OK! reported that the now-single Madonna was not shy about grinding on JT during their song, eliciting a wide, mischievous grin from Timberlake. The onstage action didn't seem to bother Madonna's alleged boyfriend, Alex Rodriguez, who was in the audience.

Madonna also got seriously political Thursday night. "I am sorry we did not win Proposition 8," she lamented, referring to the gay-marriage ban passed on Tuesday in California. "If we can have an African-American in the White House, we can have gay marriage," she told the audience, as an image of President-elect Barack Obama appeared on the big screen behind her.