Steven Tyler came out to help the Zac Brown Band wrap up their three-night stand at Fenway Park in Boston on Sunday (Aug. 9), joining the group for performances of the Aerosmith classics "Walk This Way" and "Sweet Emotion."

You can watch Tyler's appearance courtesy of some fan-shot footage, with "Walk This Way" above and "Sweet Emotion" embedded below. He made his way to Fenway shortly after returning home from Aerosmith's summer 2015 Blue Army Tour, which wrapped Aug. 7 with a gig at the Pro Football Hall of Fame's inaugural Concert for Legends in Canton, Ohio. Brown expressed his admiration with a post-show tweet:

With Aerosmith's touring obligations out of the way, Steven Tyler is presumably free to focus on his upcoming solo album, which finds him working in a country vein and has already been prefaced with the release of a leadoff single, "Love Is Your Name."

Tyler's solo label, Big Machine, happens to also be the home of the Zac Brown Band — a group whose music was on Tyler's radar before the two shared a label logo. Tyler put together a playlist of his personal country favorites for USA Today earlier this year and included Brown's "Homegrown," saying, "Country's the new rock because of people like Zac who aren't afraid to throw in a couple of good guitar licks."

He's hardly alone among his peers in his enthusiasm for Brown's work: In the recent past, the band has joined the Foo Fighters to cover Black Sabbath, made the news with its version of the Beatles' "Let It Be," teamed up with the Doobie Brothers to re-record "Black Water," and scored a crossover hit from their most recent album Jekyll + Hyde with an assist from Chris Cornell.

Watch Steven Tyler Perform 'Sweet Emotion' with the Zac Brown Band

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