Manager Alan Pardew rued a missed opportunity by striker Dwight Gayle as Crystal Palace crashed out of the FA Cup with a 2-1 defeat to Liverpool on Saturday.
Pardew was disappointed with his own side's performance but believes the result could have been different had Gayle not spurned a one-on-one chance with Palace already leading 1-0.
"That turned out to be a pivotal moment," Pardew said. "Dwight, in those situations, is usually very efficient -- I was surprised he missed because he's very clinical.
"We would have been very difficult to beat if we'd got the second goal but it didn't go in and of course the game was different."
Pardew described the cup exit as an "opportunity missed" but felt Liverpool deserved their win.
He added: "I'm disappointed with how we played. With the ball, that was one our worst performances under me.
"We're a lot better than that and we need to prove that against Arsenal on Saturday."
Mario Balotelli set up Liverpool's winner on Saturday, but Pardew wasn't impressed, insisting the striker was lucky not to give a penalty away after obstructing Brede Hangeland in the box.
"I thought he gave a penalty away at the corner," Pardew said. "He does things like that, he had a couple of incidents that were typical Balotelli.
"I'm not here to criticise him but that's fact. But he's a good technical player and it was a great hit for the second goal.
"He showed some nice moments but I think Brendan is searching for him to truly arrive. I don't think he's arrived yet as he was at Manchester City."
Information from Press Association was used in this report.