"To follow the substitution" means to replace one thing with another and then continue with the process or activity using the new thing. Full definition
Don't follow my substitutions in this case. (epicurious.com)
Costa headed straight for the dressing room following his substitution, and he appeared to be feeling still the effects of a Sergi Gómez stamp on the foot. (intothecalderon.com)
Rodriguez received a standing ovation over the weekend after he clapped all four sides of the Bernabeu following his substitution in the 4 - 1 thrashing of fourth - placed Sevilla. (calcioinsider.com)