If, in the mid-1980s, you had been asked to pick an American band who would be playing stadiums 20 years on, you probably wouldn't have named the Red Hot Chili Peppers. The California funksters began their career playing strip clubs with socks covering their genitalia, and since then have gone through an assortment of drummers and guitarists, as well as battling with drug addiction: founder member Hillel Slovak died from a heroin overdose in 1988.
This batch of stadium dates sold out in a matter of hours, and the Chili Peppers - now abstemious yoga enthusiasts - certainly seem in a position to enjoy their fame. Singer Anthony Kiedis, with his tawny hair, bare chest and bondage mitts, looks more like Conan the Barbarian than a man who has spent much of the past two decades partying hard. Endearingly, his ever-energetic bandmate Flea has stickers of his favourite bands stuck to his bass. The most compelling member, however, is guitarist John Frusciante, who gives opener Don't Stop a sophisticated, bluesy intro and sings falsetto on a cover of Donna Summer's I Feel Love.
This drive to entertain is visible throughout; if Kiedis is sick of playing MOR lament Under the Bridge, he doesn't show it, investing the band's best-known song with dignity. The lascivious heavy funk of the band's early work is largely left aside in favour of their later, mid-paced material. As the hearty roar that greets By the Way attests, it's a popular move, although a few more stompers wouldn't go amiss: Zephyr Song's comforting coda is more mid-afternoon nap than rock'n'roll.
The closing track, Give It Away, is enough to banish most doubts: Kiedis, Frusciante and Flea pogo their way into the long twilight while the crowd bounds. Populism has its own rewards, and the Chili Peppers are reaping them.
· At the City of Manchester Stadium on Friday. Box office: 0870 062 1894.