West Ham United striker Lucas Perez has defended himself in the wake of media reports he refused to warm-up and come on as a substitute during his side's 3-1 win over Everton in the English Premier League.

The Spaniard was on the bench and looked like he was about to replace the injured Marko Arnautovic in the second half of Sunday's match, but manager Manuel Pellegrini brought on midfielder Michail Antonio instead.

Perez was then captured by TV cameras in conversation with West Ham's goalkeeping coach Xavi Valero on the bench and some sections of the British media reported he had refused to play.

"Given the false information spread by the media that has affected my image, I am obliged to explain the only truth: I have never ever refused to warm-up in my whole career, let alone play a match," Perez said via Twitter on Monday.

"In the moment that Marko got injured, I was on the bench after warming up. The coach called me to go out to play, however having realised that it was faster to substitute Antonio in, who at that moment was warming up, he changed his decision.