Rafael Benitez admitted his promotion-chasing Newcastle side were not "mentally ready" after succumbing to a 3-1 defeat at Ipswich.
Newcastle were put to the sword by the Suffolk side's best display of the Sky Bet Championship season, capped by goals by Freddie Sears, David McGoldrick and Emyr Huws.
It was a performance befitting Sir Bobby Robson Day, celebrated by both sides, but Newcastle had precious little else to cheer as they remain stuttering rather than strolling towards the Premier League.
Benitez said: "I am concerned about the change in my team's performance from Leeds on Friday to the performance today.
"We know we have to win our games and now we have to change and improve.
"We knew it was going to be this kind of game but we were not ready - it seems we were not mentally ready.
"We made mistakes and we got paid for it. We have to all take responsibility, we win together and we lose together.
"I won't blame my players in press conferences. They know what I told them at half-time and at the end, we know something was wrong and now we have to analyse and change quickly."