Witness Recalls Alan Thicke's Final Moments: 'We All Thought He Was Going to Be OK'

Darin Mathewson said the TV icon was actually joking with his son Carter after collapsing on the ice.

The manager of the skating rink where Alan Thicke was set to play a game of hockey before tragedy struck said he was cracking jokes after he collapsed on the ice.

Read: Robin Thicke Pays Tribute to His Actor Dad Alan After His Sudden Death at 69: 'The Greatest Man I Ever Met'

Darin Mathewson, who manages the Los Angeles rink, told Inside Edition: “He kind of gave everyone a thumbs up. Carter was with him and very upset, which is understandable to see your dad like that. Alan's color was not great at that point but he was talking and looking around.”

The Growing Pains star's 19-year-old son, Carter, was with him at the time. At one point, it looked like the 69-year-old was going to make it. He was even joking around as he was being transported to the hospital.

“As they were putting him on the gurney and rolling him out he said to his son, ‘stop, stop, take a picture of me over here — make sure you get the rink in the background.’ That's the kind of guy he was so we all thought he was going to be ok,” Mathewson told Inside Edition.

Thicke was rushed to St. Joseph Medical Center, located just one mile away from the rink.

Thicke was seemingly in excellent shape. Footage from Hockey Night in San Diego shows him previously competing on the ice with a smile on his face.

Now many are asking how the 69-year-old could collapse without warning from a massive heart attack.

Cardiac surgeon Dr. Mehmet Oz, told Inside Edition that the cold temperature in the rink may have contributed to Thicke's apparent heart attack.

“When you’re in a cold place, an ice rink, your arteries are squeezed up like that. Then you get on the ice and warm up and your heart isn't ready yet. It's a bad combination. That's why as a heart surgeon, this is my busiest time of year. We have 50 percent more heart attacks in the wintertime than the summer time,” Dr. Oz said.

Four hours before his death, Thicke tweeted about his guest appearance on the Netflix series Fuller House.

He wrote: "Season 2 Fuller House looking good. I even like the ones I’m not in!"

Read: Mel Brooks, Sarah Silverman, Jim Carrey Remember Gene Wilder: 'If There's a Heaven He Has a Golden Ticket'

Following his passing, Carter wrote: “Today I lost my best friend and my idol, and the world lost one of its finest. You are a legend and I love you pops. Until next time.”

His other son, singer Robin Thicke, called his father, “the best man I ever knew. The best friend I ever had.”

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