Manchester United boss Ole Gunnar Solskjaer says his new contract will mean little if they perform poorly this season.
Solskjaer recently penned a new three-year contract but insisted that security counts for nothing if he does not deliver success.
"It doesn't matter if you have a 10-year contract or a one-year contract, if you don't do well off you go," the Norwegian said.
"You feel under pressure all the time. At this club, with this responsibility, it's not just clinging onto your job it's about the responsibility that's in my hands."
Solskjaer also said: "I feel us and Chelsea have spent well, worked well and we should look at ourselves as potential challengers.
"It feels like this season coming up is one of the strongest Premier League seasons. Of course it's been City and Liverpool fighting it out for a few years. Anyone who ends up above last year's champions will be champions.
"I'd rather be an optimist and be wrong than be a pessimist and be right. Of course these boys can, with a maximum effort and maximum sacrifice. We want to start winning trophies and we've laid the foundations."
