Gwynn had two operations for cancer in his right cheek between August 2010 and February 2012. The second surgery was complicated, with surgeons removing a facial nerve because it was intertwined with a tumor inside his right cheek. They grafted a nerve from Gwynn's neck to help him eventually regain facial movement.
Gwynn had said he believed the cancer was from chewing tobacco.
San Francisco Giants third base coach Tim Flannery played a long time with Gwynn and then coached him. Flannery says he'll "remember the cackle to his laugh. He was always laughing, always talking, always happy."
"The baseball world is going to miss one of the greats, and the world itself is going to miss one of the great men of mankind," Flannery said. "He cared so much for other people. He had a work ethic unlike anybody else, and had a childlike demeanor of playing the game just because he loved it so much."
In a rarity in pro sports, Gwynn played his whole career with the Padres, choosing to stay rather than leaving for bigger paychecks elsewhere. His terrific hand-eye coordination made him one of the game's greatest contact hitters. He had 3,141 hits, a career .338 average and won eight NL batting titles. He excelled at hitting singles the other way, through the "5.5 hole" between third base and shortstop.
Gwynn played in the Padres' only two World Series and was a 15-time All-Star.
He homered off the facade at Yankee Stadium off San Diego native David Wells in Game 1 of the 1998 World Series and scored the winning run in the 1994 All-Star Game. He was hitting .394 when a players' strike ended the 1994 season, denying him a shot at becoming the first player to hit .400 since San Diego native Ted Williams hit .406 in 1941.