Mallex Smith sprinted to Seattle this season after stealing exactly 40 bases for Tampa Bay in 2018. He has 39 this year, making the 40 steals milestone eminently reachable for him.
Including Smith, there have been 24 American League players since 2000 to steal 40 bases in a season. Some of them are future Hall of Famers and some are multiple-time All-Stars, while others are AL Central World Series heroes, cult figures, That Guys, or in the case of one particular speedster, a noted villain for an entire region of baseball fans due to an infamously terrible contract.