But Gardner will continue to do it, because in his case, he feels it allows him to get to first base quicker.
"Guaranteed," he said.
Don't believe him?
"If somebody wants to argue with me about it," Gardner said, "I'll sit them down in front of a computer for two minutes and show them that I do get there faster."
Due to the risk of injury, Gardner will only dive head-first into first base if he feels it's absolutely necessary to beat a throw, which he has done at least a couple of times in this four-game series against the White Sox.
Many in baseball are against diving head-first into first base, not only because of the injury risk, but because they feel it's actually slower than running through the bag.
But while that may be the case for many, Gardner feels he actually gets to first base quicker, because when he runs through it "there's a little bit of time when I'm in the air, waiting to come down to first base. That's like wasted time," he said.
Gardner has pored over the tape, has timed himself down the line, and has noticed he gains extra time by diving in. It may only be by a split second, but it's enough to make an appreciable difference for a speedster who makes a living with his legs.
Gardner came into the finale against the White Sox on Thursday batting .280 with a .359 on-base percentage, and tied for the American League lead with 33 steals. In 21 second-half games, he's hitting .329 with a .398 on-base percentage and 10 steals.
A lot of that success has come on infield singles he has been able to beat out in just the nick of time. Gardner -- who missed over a month in 2009 after breaking his thumb sliding feet-first -- feels you can get hurt doing anything in this game.
And the advantage of sliding head-first into first base is worth the risk.
"I try not to ever do it if I don't have to," Gardner said. "But if a guy is coming over and he's covering the bag and I feel like I can dive head-first and have my hand touch first base before his foot touches first base, I'm going to do it."