Domínguez Pérez-Perunovic, World Blitz Championship, round ten, 13 October 2015.
Position after 64. Qa7-e3+.
Good effort on Perunovic's part. Having already in the same position chosen to retreat the king to f7, he rejects the opportunity to take the draw by repetition, not to mention more than one win (including the one that would start with ...Kf7) and picks out The Worst Move On The Board instead.
See - and for that matter, hear - him do it here. (Blitz Day 1: Rounds 1-11, start at 5:05:56.)
[Thanks to John Cox]
[Worst move index]