Coldplay paid tribute to Tom Petty during their Monday concert in Portland, Oregon as the rock legend was taking his final breaths.

Chris Martin and co. covered Petty's epic "Free Fallin'" with R.E.M. guitarist Peter Buck at the Moda Center. They also opened the gig with a moment of silence for the Las Vegas mass shooting victims.

The group does a good job, although Martin can't match Petty's high notes.

TMZ broke the story ... Tom suffered a fatal cardiac arrest Sunday night and died later in the hospital. He was 66.