He played college football for the Colorado Buffaloes and was selected by the Cardinals seventh overall in the 1974 NFL draft.
[1] In 1978, Jackie Smith joined the Dallas Cowboys, leaving Cain the top tight end on the Cardinals' roster.
[4] A devout Christian, Cain used his time that season to read the Bible, and prayed that after recovering from the injury, he would go on to become an All-Pro tight end.
[5] On July 22, 1979, his 28th birthday, at about 8:30 p.m., Cain suddenly collapsed during a no-contact training camp practice at Lindenwood College in St. Charles, Missouri.
[2][4][6] His death was found to be due to an extremely rare congenital heart problem, undetectable except by autopsy, which was exacerbated by strenuous exercise.