One of the greatest contact hitters of all time and notoriously hard to strike out, Keeler has the highest career at bats-per-strikeout ratio in MLB history, averaging 63.17 at bats between each strikeout.

He played baseball from an early age, and as a freshman served as captain of his high school team.

[3] Keeler's advice to hitters was "Keep your eye clear, and hit 'em where they ain't"—"they" being the opposing fielders.

Keeler had an amazing 206 singles during the 1898 season, a record that stood for more than 100 years until broken by Ichiro Suzuki.

He was one of the smallest players to play the game, standing 5 feet 4½ inches and weighing 140 pounds (64 kg), resulting in his nickname.

[11] In the 1899 season for the Brooklyn Superbas, in 570 at bats, Keeler struck out only twice, setting an AB-per-K mark of 285, an MLB single-season record.

Bill James speculated that Keeler introduced the hit and run strategy to the original Orioles and teammate John McGraw.

In one of the most one-sided trades in baseball history, Hanlon obtained Dan Brouthers and Keeler from Brooklyn in exchange for Billy Shindle and George Treadway.

Keeler remained in Brooklyn and did not actually jump to the new league until 1903, when he signed with the New York Highlanders (renamed the Yankees in 1913).

[18][19] After his retirement, Keeler was a scout and coach for the Superbas and the Boston Braves, as well as Brooklyn's Federal League team, the Tip-Tops.

His real estate lost value in the post-World War I economic recession, and by the time of his death, his brothers and he had to sell their childhood home.

Keeler is mentioned in the story "Hit 'em where they ain't" by Robert Ruark and as well in the poem "Line-Up for Yesterday" by Ogden Nash.

[...] One of his principal slogans is to call out: "Now shust hit der ball vere dey ain't!"