Flowers ring the base of the Tony Gwynn statue outside Petco Park (Lenny Ignelzi / AP)

San Diego Padres slugger Tony Gwynn, who died Monday morning at the age of 54, believed that his lengthy habit of using smokeless tobacco was to blame for cancer of the mouth and salivary glands that took his life.

Gwynn, whose career spanned 20 years, played at a time when baseball players typically sported a cheekful of tobacco, spitting a black stream of juice during games and in the dugouts. There was no doubt in his mind that the disease caused him to require two lengthy surgeries in an attempt to arrest the cancer.

“Of course, it caused it,” Gwynn said. “I always dipped on my right side.”

Gwynn had been ill for four years, but his death was a jolt and now the question is whether it will be a wake-up call. Much has changed since Gwynn was a player. Since the 2011 collective bargaining agreement, Major League Baseball has prohibited teams from providing tobacco products to players and encourages clubhouse attendants not to get them for players. Players are not allowed to have tobacco tins in the pockets of their uniforms (no more of those telltale round impressions). Players cannot do TV interviews while using smokeless tobacco and violators of any of these rules can be fined.

While he was recovering from Tommy John surgery three years ago, Washington Nationals pitcher Stephen Strasburg decided to quit the habit and acknowledged to The Post’s Adam Kilgore that it wasn’t easy.

“I’m still in the process of quitting,” Strasburg, 22, said. “I’ve made a lot of strides, stopped being so compulsive with it. I’m hoping I’m going to be clean for spring training. It’s going to be hard, because it’s something that’s embedded in the game.”

Use among players has remained relatively steady, even though use of smokeless tobacco is banned in the minor leagues on the field, in clubhouses and while teams are traveling. College and most amateur baseball associations ban it, too, and congressional hearings were held in 2010.

“It’s nasty stuff,” Gregory Connolly, a Harvard professor who has lectured major league players and testified before Congress on the ills of smokeless tobacco, told Kilgore. “There’s no other way to look at it.”

The question of whether to ban use of tobacco will come up again in 2016, when labor negotiations begin. Tony Clark, executive director of the Major League Baseball Players Association, said in a statement after Gwynn’s death was announced:

“I am deeply saddened to learn that Tony Gwynn has lost his courageous battle against cancer. Since his diagnosis, Tony displayed the same tenacity and drive in his fight against this horrible disease that he brought to the plate in every at bat of his Hall of Fame career.”

Will his death still resonate as strongly as it does now?

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