A disappointed Rafael Benitez told his Newcastle players to calm down and get to work following a 1-0 defeat to Fulham in the Magpies' first Championship fixture in six years.
Newcastle's campaign to win promotion back to the Premier League at the first attempt got off to a faltering start after they failed to cancel out a first half header from Fulham striker Matt Smith at Craven Cottage.
Benitez, who has never managed at this level before, said his players became anxious following the goal and could not plot a route back into the game.
"We didn't play at the level we expected," admitted the Spanish manager. "We have to improve. These games will be a wake up for everyone."
"You could see when we were losing 1-0 a little anxiety [in the Newcastle team]. We have to manage it much better and have a clearer idea of what we want to do. Be more calm and do things much better.
"We were not keeping the ball properly, that's clear. Also we were not winning the second balls in the middle."
Newcastle, who were without Moussa Sissoko, may look to add to their squad before the transfer window shuts before the end of the month.
Benitez claimed the Real Madrid target was left out of the squad as he was not match fit, but suggested he was still looking at potential signings.
"We have to keep working," said. "We need something more, maybe in terms of players, but especially in terms of working hard."
"We had a lot of players who have played in the Championship. We just need to manage the situation better.
"When you are bringing in players and players are leaving you need a bit of time [to gel]."
The former Liverpool boss was particularly frustrated at conceding a goal from a corner, something he said his team had been paying special attention to in training.
"It was disappointing to concede because this goal was something we had been working on in the week," he said.