Crystal Palace boss Sam Allardyce was left frustrated at the officials after Seamus Coleman's late strike condemned his side to a fourth straight Premier League defeat in a 1-0 loss to Everton.
Coleman thumped home Everton's winner in the 87th minute at Selhurst Park, leaving Allardyce still in search of his first league win as Palace manager, with the London club two points adrift of safety.
Although Everton dominated much of Saturday's encounter, Allardyce believes referee Anthony Taylor's refusal to allow Palace to substitute off the injured Jeffrey Schlupp was the reason for the defeat.
"We showed a lot of resilience, and I think they weren't done by their own downfall really," the former England manager said. "We were down to 10 men because Schlupp was off injured and we couldn't get a substitute on, and I think Coleman was offside.
"So we deserved the 0-0 and it's hugely disappointing we didn't get that. I don't think we were to blame for the defeat.
"Being in the bottom three does bring pressure, so we're going to have to live with that. But I'm encouraged by the way we're working."
Having now claimed just one point from his five league games in charge, Allardyce acknowledged that Palace require further reinforcements, but insisted the club will not panic in the transfer market.
"It's important to get a few players in. You'll see more business at the bottom end of the table than at the top," Allardyce added.
"I can pick from a 100 players available tomorrow, but how many of them will be good enough is the issue. You can't panic and buy somebody for the sake of it.
"If we can find a player who is better than what we have we will bring them in, if we can."
Everton, meanwhile, have now won three league games in a row for the first time since September, and Ronald Koeman was delighted with his side's display as they moved within five points of the top six.
"It was well deserved. It was difficult at the start but when we controlled the game we were the better team, with the best chances," the Dutchman said.
"Their goalkeeper [Wayne Hennessey] was outstanding, and maybe we made it too easy for him times.
"After the win against Manchester City, everybody expects an easy win at Palace, but it was very difficult so I am very proud."