Sammy Hagar joined his pal Kenny Chesney during a concert over the weekend, giving a huge group of country-music fans the chance to sing along with "I Can't Drive 55." Watch their performance from Levi's Stadium in Santa Clara, Calif., above.

"I couldn't believe hearing 50,000 people scream '55' at the top of their lungs," Hagar said at his website. "Certainly one of the highlights of my year musically so far."

Chesney has been a regular guest at Hagar's birthday bash in Cabo San Lucas, and even wrote his chart-topping country hit "Beer in Mexico" while hanging out by the ex-Van Halen frontman's pool. He appeared on a Aug. 6 bill that also included Miranda Lambert, Sam Hunt and Old Dominion. "Miranda Lambert was great, as well – two of Samantha's favorites," Hagar says, referencing his youngest child with wife Kari.

Hagar was set to return to his Maui home afterward, where he no doubt hopes his latest creative outburst will continue. He recently unveiled a solo track and has also mentioned new material from Chickenfoot, the long-dormant supergroup featuring Joe Satriani, Chad Smith and Michael Anthony.

During a February episode of Dan Rather's The Big Interview, Hagar played "The Inner Child," which he described as a "little lullaby." The new Chickenfoot track, which Hagar talked about last fall, is titled "Before I Die." He called it "the coolest song that we’ve maybe ever had."

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