Tony Pulis lamented West Brom's defensive mistakes after seeing his side let a two-goal lead slip in a 3-2 Premier League defeat to Everton on Monday.
Saido Berahino had put West Brom in front late in the first half, with Craig Dawson doubling the hosts' advantage with a header nine minutes after the second-half restart.
But Romelu Lukaku provided an instant reply to Dawson's goal and, after setting up Arouna Kone for the equaliser, completed the turnaround in the 84th minute.
Pulis felt Kone was offside for Everton's second but was quick to criticise his players for failing to see out the game from a commanding position.
"We get the second goal and all we've got to do is sit tight and be nice and solid for 10 minutes," Pulis told Sky Sports.
"Everton have scored off a couple of crosses, I think the second goal was offside. I don't know what the linesman was doing stooping and looking inside instead of stooping and looking outside.
"The defending off the set plays was awful. We were still celebrating [after Dawson's goal], you have to get the ball back and take the sting out of the game. We gave them the opportunity.
"We had the game in our hands and we gave it to Everton really."
Pulis also confirmed Jonas Olsson - brought off in the 27th minute - had suffered a groin injury, giving West Brom more problems at the back after Gareth McAuley missed the game with a calf problem.
