"Better late that never!" singer David Lee Roth proclaimed from the stage.
Eddie Van Halen – who battled tongue cancer in 2002 and went to rehab last year – looked healthy as he jumped up and down and ran around the stage throughout the entire show.
When the concert dates were postponed last month, the band issued a statement that Van Halen, 53, was "undergoing a battery of comprehensive medical tests to determine a defined diagnosis and recommended medical procedures."
At the time his ex-wife Valerie Bertinelli quickly dismissed rumors that he was back in rehab, while their 17-year-old son Wolfgang, who's playing bass on tour, told PEOPLE three weeks ago, "Don't listen to the rumors – he's doing great – seriously!"
Thursday, Van Halen happily posed for photographers at the L.A. airport with his girlfriend of almost two years, Janie Liszewski, who's also the band's publicist.