Guitar in hand, the singer performed a slowed down cover of the Eagles’ “Take it Easy” as fans sang along.
Frey died on Monday at the age of 67. The band confirmed his death in a statement on their official website.
“Glenn fought a courageous battle for the past several weeks but, sadly, succumbed to complications from rheumatoid arthritis, acute ulcerative colitis and pneumonia,” read the message signed by band mates, including Don Henley and Joe Walsh, as well as family.
“I knew him for 50 years,” Seger said. “He was a great kid. I always kind of thought of him as my baby brother, a little bit. He was f—ing brilliant. He was a joy to be around. I always looked forward to seeing him. It was always memorable. He had an amazing sense of humor and was just smart, whip-smart.”
Immediately following the news, celebs including Steve Martin, Kiss band members Paul Stanley and Gene Simmons, and Brad Paisely, among others, took to Twitter, mourning his death.
“My mom used to play Eagles records for me on my way to grade school,” a tweet from Justin Timberlake said. “We lost one of the greatest songwriters ever today #RIPGlennFrey.”