Jiri Procházka loses rematch with light heavyweight champion Alex Pereira
He fell in Las Vegas, as he did last November, in the second round by TKO. Pereira stopped Walk with a devastating head kick early in the fight.
Defending champion Pereira first hit his thirty-one-year-old opponent hard at the end of an otherwise even first round, then quickly ended the fight at the start of the second round. The judges stopped him after 13 seconds.
Prochazka lost the second of six fights in the UFC, although Pereira remains his only defeat in eight years.
Two years ago in Singapore, he defeated Glover Teixeira of Brazil in a great fight.
But less than six months later, he relinquished the championship belt because he was injured in training and was unable to fight Teixeira in the scheduled rematch.
The second Prochazka-Pereira fight was originally scheduled to take place at the end of the holiday season or in the fall, but after star Irishman Conor McGregor was injured and forced to call off his fight with American Michael Chandler, the UFC organisation reached out to the welterweight stars at the last minute.
In the end, Pereira handled the shortened preparation better and defended his title.