West Ham manager Sam Allardyce said he believes Eden Hazard's decisive goal in Chelsea's 1-0 defeat of the Hammers should not have stood.
"I've looked at the goal and it was offside," Allardyce said after Wednesday's match.
Hazard nodded home a Ramires cross to keep Chelsea five points clear of chief challengers Manchester City.
But according to the West Ham boss, Hazard's head start was even bigger than that of Kevin Nolan, who had an 89th-minute goal nullified in the Hammers' 2-1 loss at Manchester United back in September.
"Kevin Nolan was offside at Old Trafford [in September] when we scored for 2-2. There was half an inch of his nose offside and they said that was offside," Allardyce said. "There was about six inches of his [Hazard's] body offside this time and they said it's onside."
Allardyce also lamented the fact that Wednesday's loss continued a dispiriting run of form for his side, which has now won just once in their last 11 tries.
"I thought that we gave a fantastic performance today," he said. "We really wanted something out of the game. We got a great performance and we've got to take a lot of positives out of that.
"Couldn't have asked for any more entertainment, everybody, I don't think. Terrific game of football.
"Just we're the wrong side of the result, sadly. Keep playing like that and we'll start winning again."