Fig. to be involved in something of large or important proportions. (Alludes to playing a professional sport at the highest level.) You had better shape up if you want to play in the big leagues.The conductor shouted at the oboist, "You're playing in the big leagues now. Tune up or ship out."
in. to become involved in something of large or important proportions. The conductor shouted at the oboist, “You’re playing in the big leagues now. Tune up or ship out.”