There's nothing better at a concert than hearing the lead singer say something like, "We'd like to bring out a special guest to help us out tonight." You can feel the excitement in the venue as the crowd tries to figure out who will appear from the wings, knowing that you're getting something special and unique.

Moments like those seem to happen every time a rock legend plays London's prestigious Royal Albert Hall. On Wednesday (June 20), Steve Winwood sat in with Tom Petty and the Heartbreakers midway through his set on a couple of his classic tunes. Winwood opened up for Petty on their 2008 North American tour.

First he sang Blind Faith's 'Can't Find My Way Home,' which was No. 94 on our list of the Top 100 Classic Rock Songs. Then he sang 'Gimme Some Lovin,'' the 1966 breakthrough hit he had in 1966 as a member of the Spencer Davis Group.

Petty's two-night stand at the Royal Albert Hall marked the first Heartbreakers concerts in the U.K. in 13 years. His last performance in Britain was the star-studded tribute concert for his friend George Harrison in November 2002. He will headline the Isle of Wight Festival tomorrow (June 22).

Watch Steve Winwood and Tom Petty + the Heartbreakers Sing 'Can't Find My Way Home'

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