I Got It (1889)

“‘Robbie’ worked one of his tricks, but it availed him nothing.  When he sent up a high foul fly, he whispered into Baldwin’s ear ‘I’ve got it,’ and the ‘Kid’ thought it was Viau who spoke, and Robinson’s life was saved.  He sent the ‘Kid’ another that made connections.”  St. Louis Republic, April 20, 1889 [Richard Hershberger]

No earliest use given in Dickson Baseball Dictionary