John Daly, Gavin DeGraw sing Tom Petty's 'I won't back down'

On Tuesday, legendary rock star Tom Petty passed away at the age of 66.

Over the last few decades, Petty pumped out a number of hit songs. One of those was "I won't back down."

On Thursday evening at a concert following the first round of the PGA Tour's 2017-18 season-opening Safeway Open in Napa, Calif., musician Gavin DeGraw brought the PGA Tour's resident rock star -- John Daly -- up on stage to pay tribute to Petty with a cover of "I won't back down."

You can see it here:

Daly's loves being on the stage whether it's with famous friends like DeGraw or Darius Rucker, or on his own.

In fact, in the summer of 2014, Daly's song "Hit It Hard" hit the airwaves:

If you know anything about Daly -- a two-time major winner -- his favorite song to perform is "Knockin' on Heaven's Door":