On The Ball Meaning

(sports) Being in control of the ball.

Example:   If I had been more on the ball I would have asked when he called me.
2010 December 28, Kevin Darlin, “West Brom 1 - 3 Blackburn”[1], BBC:
  ...Rovers were also aided by some poor defending from West Brom, whose lapses at the back undid their excellent work on the ball and condemned Roberto di Matteo's Baggies side to a third straight defeat.