Manchester United defender Chris Smalling believes Dimitri Payet should have been dismissed shortly before his superb free-kick at Old Trafford on Sunday.
The Frenchman, who had already been booked, went down in the box under a challenge from Marcos Rojo, but the referee waved away the visitors' penalty claims.
Payet later put the Hammers in front in the FA Cup quarter final against United, but Smalling says the 28-year-old shouldn't have been on the field following a 'dive'.
"I've heard there was no contact and, to be fair, it should have been another yellow card," he said.
"But there are many decisions in a game and it's one that didn't go our way.
"I think if they're not going to give a penalty, then it has got to be diving, really, hasn't it?
"I think more often than not, if you dive you do get a yellow card. Obviously on this occasion it didn't happen but we won't pin the game on the one decision."
