Def Leppard kicked off their 2025 run of live dates over the weekend without guitarist Viv Campbell. The English rock legends performed in Leon, Mexico on Saturday (January 18), and did so without Campbell, who sat out the gig while he was recovering from his recent cancer treatment. John Zocco – Phil Collen’s guitar tech as well as Def Leppard’s photographer – sat in for the ailing 62-year-old rock veteran. “Vivian Campbell cannot be with us tonight,” frontman Joe Elliott announced to the crowd. “He’s just recovering from some treatment for his cancer. So, please say hello to the guy that’s standing in for him tonight, Mr. John Zocco on guitar.” Campbell was initially diagnosed with Hodgkin lymphoma back in 2013, and while he announced he was in remission the following year, the cancer returned in 2015 and the musician has been fighting it ever since. Def Leppard’s next scheduled performance is on May 15 in Puerto Rico. (Ultimate Classic Rock)