West Brom's Jerome Thomas claims Lee Mason was wrong to award Liverpool an early penalty in the Baggies' 2-0 defeat at the Hawthorns.
The winger was adjudged to have tripped Luis Suarez in the box and Mason pointed to the spot despite protests from the West Brom players.
Charlie Adam dispatched the spot-kick after a long delay to set Liverpool on their way to victory.
Thomas told the Birmingham Mail: "It didn't think it was a penalty at the time and I don't even think the referee did.
"It didn't look like he was going to give it and then the linesman flagged and I guess that's what made up his mind.
"I always thought the assistants were exactly that. I thought they were there to assist if the referee couldn't see it.
"Not only was the referee close enough but he seemed to have seen it and didn't think it was a penalty."