Surprises, Rap’s New Class Take Over Summer Jam XX

Lil Wayne, Rick Ross, Nicki Minaj, Mariah Carey and Lil Kim were among the guest stars of Sunday’s show at the MetLife Stadium in East Rutherford, N.J, where Beyoncé and Jay-Z watched from backstage. Kendrick Lamar, 2 Chainz, A$AP Rocky and French Montana performed sets that electrified the excited crowd. Wu-Tang Clan hit the stage and were solid, though the energy of the audience – filled with a good number of twentysomethings – dwindled throughout the set.

Here’s a breakdown of the highlights from Summer XX, which also featured Chris Brown, Miguel, Wale, Fabolous and Joe Budden.

SURPRISE: IT’S WEEZY F. BABY AND RICKY ROZAY

No offense to French Montana, but Summer Jam XX would have been disappointing if the rapper closed the five-hour concert alone. Thankfully, he brought out Rick Ross – and then to the largest roar the audience gave Sunday night – there came Lil Wayne. They performed the addictive hit “Pop That” as the crowd sang along and jumped up and down.

Bringing out a special guest (or guests) was the night’s theme: Minaj earned cheers when she helped 2 Chainz on “I Luv Dem Strippers” and “Beez in the Trap,” Fabolous brought out fellow Brooklynite Lil Kim, and R&B singer Miguel had J. Cole and Mariah Carey help him with his set.

A$AP Rocky, 24, said he’s a big fan of ‘90s hip-hop, namedropping acts like Wu-Tang Clan, N.W.A., UGK and Three 6 Mafia as favorites. But he wasn’t all talk: Quickly after he spoke about his rap heroes, Bone Thugs-N-Harmony joined him onstage.

HIP-HOP’S NEW CLASS TAKES OVER

Hot 97 was celebrating 20 years of Summer Jam, but rappers in their twenties dominated the annual concert. Hip-hop’s new class, including Kendrick Lamar, A$AP Rocky, French Montana and 2 Chainz (he’s 35, but appeals to a younger audience), kept the crowd of thousands on their feet, performing back-to-back jams that have controlled urban radio in the last year.

Lamar, who is the critical darling of the bunch, was the best of the youngsters: He was cool onstage as he rapped songs from his near-platinum major label debut, “good kid, m.A.A.d city,” including “Poetic Justice” and “(Expletive), Don’t Kill My Vibe.” He left out “Swimming Pools (Drank),” though that song would have been appropriate since the audience was drenched after it rained – several times – at the MetLife Stadium.

2 Chainz entered the stage rapping his verse from Kanye West’s “Mercy,” and he followed that with a number of radio hits, including “I’m Different,” ‘‘Birthday Song” and “No Lie.” A$AP Rocky was wild onstage, and rap’s new class showed the brotherly love when he was joined by Lamar and 2 Chainz for “(Expletive) Problems.”

THAT WAS A LITTLE AWKWARD

Nicki Minaj is obviously confident – not many people wear multicolored wigs like she does. But on Sunday, things were just a little awkward for the rapper, and for a couple reasons.

Last year Minaj backed out of headlining Summer Jam after Hot 97’s Peter Rosenberg dissed the rapper and her dance-pop hit, “Starships.” Minaj debuted in 2009 deeply rooted in rap, but later she began to sing on her songs and found success with electronic-based tunes and collaborations with David Guetta. But the 30-year-old returned to the Summer Jam stage – for mere minutes with 2 Chainz – in a curly blond wig and blue jeans. She exchanged words – they seemed cordial – with Rosenberg onstage after performing.

Minaj also performed on a stage where her enemies were also present: Her fellow and former “American Idol” judge, Mariah Carey, was in the building, as was Lil Kim, who feuded with Minaj when the rapper came on the music scene.

Who’s got backstage video?

TOO YOUNG TO APPRECIATE?

Wu-Tang Clan, who also celebrated 20 years in music Sunday, showed no signs of slowing down with a set that felt both fresh and nostalgic. Too bad the crowd didn’t think so.

The young audience grew excited during small parts of the rap group’s set, and Ghostface Killah, Method Man, RZA, Raekwon and the other members seemed to notice.

“All we ask is that the energy we give to you, give it back to us,” Method Man told the crowd.

“I think New York forgot about us a little, man,” RZA said later.

Despite some of the crowd’s disinterest in the veteran group, they blazed the stage, performing jams like “Wu-Tang Clan Ain’t Nuthing ta (Expletive) Wit,” ‘‘Da Mystery of Chessboxin’“ and “C.R.E.A.M.”

Kids, do your rap research.

HIP-HOP’S COUSIN: THE R&B TREATS

Summer Jam is a rapper’s show, but R&B held its own, thanks to Miguel and Chris Brown.

Miguel was silky, performing hits like “Sure Thing,” ‘‘How Many Drinks” and “Adorn” – all as the crowd sang along. He earned more points when he brought out diva Mariah Carey to sing her new single, “Beautiful,” where he is featured.

Brown, who has rapped on some of his songs, was bold when he hit the stage: He started with the European-flavored “Beautiful People,” where he was backed with futuristic dancers and auto-tune. The crowd didn’t fist pump, but they were pumped.

Brown was quick on his feet when performing “Fine China” and slowed things down for “Don’t Judge Me.” And while he first wore a Yankees jersey, he took it off to sing – wait for it – his R&B hit “Strip.”