Pulis's men took the lead on 11 minutes when Wayne Rooney headed into his own net, but the hosts stormed back to record their 10th consecutive win over the Potters at Old Trafford.
"One or two players didn't play as well as they can do today and we need them to play at their best," said Pulis.
"Against the top teams, if you switch off they kill you. We were sloppy defending and the times of the goals killed us."
Stoke have not won a Premier League away match since January.