Police found Daniel Kerrigan, 70, unconscious in the kitchen of his Stoneham property on Sunday (24Jan10) after receiving an emergency call reporting a "sudden death".
The athlete's brother, Mark - who was also at the house - was hospitalised for an unspecified injury and police are now looking to charge him with assault and battery on an elderly person, reports the New York Daily News.
Reports suggest there was a struggle between father and son before Daniel collapsed.
His wife, Brenda, is convinced her husband suffered a heart attack but authorities have yet to verify her claim.
She tells the Boston Herald, "My husband had a massive heart attack. This is a very difficult time for me."
Mark Kerrigan, 45, is expected to be arraigned on Monday afternoon (25Jan10).