Sammy Hagar got a head start on his birthday festivities over the weekend with a pair of Las Vegas shows. Hagar, who turns 77 on Sunday, played the prelude to his annual birthday bash at the Cabo Wabo Cantina in Cabo San Lucas, Mexico, and was joined onstage Friday by Rick Springfield to perform ‘I’ve Done Everything for You’, a Hagar single that was a hit for Springfield in 1981.