But aside from doing these sorts of visualization / imagery techniques before competition, they can also be done during competition; like in between rounds. There's a book entitled Imagery in Sports and Physical Performance, which was edited by Anees A. Sheikh and Errol R. Korn, which gives great insight into this practice:
So for a fighter, he or she can take the advice that the corner is giving them in between rounds, and simultaneously make a mental movie of executing said techniques. While drinking water and taking deep breaths, one can also multi-task in that minute break in between rounds to visualize executing the plan; whether it's landing the jab, throwing a high kick, or a certain set up to a takedown. Whatever game plan tips that one's corner is doling out in between rounds, those can be instantly materialized in the mind to make the practice of those techniques in the cage moments later, easier to execute.