The secret trick that led to accusations of Boston Red Sox starter Clay Buchholz throwing a spitball has an ancillary benefit: It prevents skin cancer, too.

Two veteran pitchers and one source close to the Red Sox told Yahoo! Sports that about 90 percent of major league pitchers use some form of spray-on sunscreen – almost always BullFrog brand – that when combined with powdered rosin gives them a far superior grip on the ball.

View photos

"Sunscreen and rosin could be used as foundation for houses," one American League pitcher said. "Produces a tack, glue-like substance that engineers would be jealous of."

During Buchholz's May 1 start against Toronto, Blue Jays color commentator Dirk Hayhurst said on Twitter the right-hander was "loading the ball" with "slick'em painted up his left forearm." When shown video of Buchholz, Jack Morris, also a commentator for Sportsnet, said, "He's throwing a spitter."

The umpires did not check. Blue Jays players said nothing. Buchholz, who threw seven shutout innings that lowered his ERA to 1.01, denied doctoring the ball in any way.

[Also: Jays pitcher stable after liner to head | Watch: Scary situation unfolds]

All almost certainly knew the truth: BullFrog is as prevalent across baseball as chewing tobacco and sunflower seeds. Major League Baseball can't exactly ban sunscreen. And players accept it as part of the game because they don't believe it leads to crazy movement on pitches like spitters of yore.

While Buchholz declined comment through a Red Sox spokesman Wednesday, one source close to the Red Sox confirmed the team's pitchers almost all rely on sunscreen for better grip on finicky balls, particularly in cold, bad weather.

Its use dates back years, when an intrepid pitcher – patient zero is unknown – stumbled upon the most wonderful of accidents, the penicillin of pitching: pine tar for the mound.

The beauty of BullFrog is its inconspicuousness. Because it goes on clear, it can easily be mistaken for sweat. Of course, the subterfuge tends to vanish when one applies sunscreen for a game played in a domed stadium, as Buchholz did at Rogers Centre.

"Most guys are a tad more discreet about it," one National League pitcher said, "rather than put the rosin on your arm 10 times over the course of an outing."

Buchholz's right hand danced all over his body in Toronto. In the first inning alone, he put it to his mouth and wet hair close to a dozen times. Before Jose Bautista stepped to the plate, Buchholz was particularly egregious, twice tapping his non-pitching forearm, the most frequent location of BullFrog application. Controversy chased Buchholz to his next start Monday, when he allowed a season-high four runs in six innings. After the game, Buchholz told reporters: "I did the same thing I've done in all seven starts this year." A review of the TV broadcast showed him going to his mouth and hair far less frequently and not once visibly grabbing his left arm, but photos showed otherwise.

He is far from the only one who has lacked prudence. The AL pitcher noted Texas Rangers starter Yu Darvish's propensity to reach for his left arm in his near-perfect game against the Houston Astros and said almost every pitcher, if one looks close enough, is guilty of the same.

View photos

Story continues