Michigan State hockey coach Tom Anastos said he was "stunned" Monday morning when he learned of his former coach Ron Mason's death.

"It's hard to believe he won't be here anymore," Anastos said, noting the fiery enthusiasm and liveliness Mason always exuded.

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Mason died early Monday from a heart attack, his family announced. Mason led Michigan State hockey from 1980 to 2002, amassing the second-most wins in the history of college hockey for a head coach and a national championship in 1986.

Anastos played for Mason at MSU from 1981 to 1985. Hear his thoughts on his former coach in the video above.