Andy Murray has struggled with cramping during matches in his preparations for this this Grand Slam.
He told Amazon Prime he thought both he and Cerundolo were "struggling physically" during that match.
"I thought I did well considering that [the cramping], mentally," he added.
"It's not easy going into a five-set match in those conditions against a guy that makes you move a lot with what's happened recently.
"It's important to give myself a pat on the back with that stuff because it's rare that anyone else does."