You can’t make that claim with certainty.
https://www.ahajournals.org/doi/full/10.1161/CIRCRESAHA.120.316756#
Christian Ericksen is back on the soccer pitch after being dead for five minutes because they implanted a device in him. Watts team better have the shocker machine close at hand at all times
Atrial Fibrillation In Athletes: Pathophysiology, Clinical Presentation, Evaluation and Management
Depending upon what caused the AF, I'm not sure the guy should be on the pitch...
He sounds like the pro on the subject to me.