Steve McClaren insisted his job was never going to be an easy one after Newcastle United fell to a disappointing 2-1 home defeat against Watford in the Premier League on Saturday.
Daryl Janmaat scored in the second half as McClaren's men attempted to fight back at St James' Park but they were ultimately unable to recover after falling two goals down inside the first 30 minutes.
The result leaves Newcastle without a win on just two points from their opening six games in 2015-16 and with Manchester City and Chelsea to play their next two league games.
"No one said this job was going to be easy, we didn't think it would be," McClaren said to Sky Sports.
"I thought the last two games would be a test for us and we would know a lot more and we know now this is a tough job, a hard job.
"I don't think you can just quickly turn a page and change everything. Of course there is [a hangover from last season] and that has been demonstrated this week.
"The first four games we had to defend against very good teams and we had done that admirably and picked up a couple of points and looked quite solid. The last two have really been a wake-up call in terms of opening up and learning a lot of lessons. It is everything - tactical, technical, physical and mental.
"They said this was a tough job and it certainly is. It is exactly what we thought. We have been here two and a half months, you are trying to change history and a mentality.
"I have told the players to stay calm. It is a long season ahead, we knew it was not going to be easy. The players know that we have made it hard for ourselves but there is still a long way to go and a lot of football."
McClaren was encouraged by the spirit his side showed after the break against Watford, but rued the poor defending that had left them behind.
The head coach continued: "I got a reaction from my players in the second half and we had enough opportunities. The difference, as it was on Monday against West Ham, was that Watford put the ball in the back of the net.
"In the first half we didn't score. Final balls, chances... we just didn't put the ball in the net. Then we didn't defend and conceded two goals so it is an uphill battle.
"Our spirit was tremendous in the second half and we nearly got it back. We got a terrific goal through Janmaat and didn't quite have that finishing touch to come back and get what would have been a great result for us."
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