Four dozen Rawlings baseballs have been rubbed with dirt and numbered sequentially, ready to enter the game when Derek Jeter comes to the plate resting on 2999 hits. The balls, one of which will be hit for the milestone 3000th of the Yankee captain’s career, also carry a hidden marking to establish authenticity. Inexplicably the balls have not been sprayed with Driven, Jeter’s perfume.

Once Derek Jeter reaches 2,999 career hits, the marked ball will be deployed during his at-bats, one at a time, and each ball’s outcome is tracked by an Authentication staffer. The home-plate umpire and a bat boy will have the process down pat for each game. Start with four or six balls — usually four, but depending on the ump — and then go through them meticulously until Jeter strokes his 3,000th hit.

How do you decide on four dozen balls?

“It’s as needed,” said Howie Shelton, program manager for MLB Authentication, and the person who actually marked the balls. “If he takes a while, he gets maybe 12 balls into it, we’d have to mark up some more. Derek’s a contact hitter. He could foul off five, six or seven pitches, and we have to be ready.”

After 2,999, any balls are removed from play under normal circumstances — tossed out after a pitch in the dirt, or perhaps Yankees first baseman Mark Teixeira comes off the field after a 4-3 putout and flips the ball into the crowd behind the Yankees’ dugout. In that case, let’s say it’s ball No. 20 after hit 2,999. The MLB Authenticator simply marks: “20 — Teixeira throws into crowd.”