Mauricio Pochettino has warned Tottenham they cannot consider themselves title contenders after three matches as he remains concerned by performances.

Spurs have won their opening three Premier League games and made a statement with a 3-0 win at Manchester United on Monday, after which numerous players spoke of targeting the title.

But Pochettino is not happy that Tottenham have revealed this ambition before proving themselves capable of maintaining a challenge, believing his side were fortunate to defeat United.

"My mood wasn't great, I was so disappointed," he told a news conference ahead of facing Watford on Sunday. "I think we need to improve our performance. In the first half, I wasn't happy.

"We need to fight the perception. When you compare the perception and the reality, the reality was that in the first half we could concede one, two, three goals. But the team showed character and in the second half we were much better, the team dominated.

"If we want to fight for big things, before we talk to the media or the fans, we need to try to improve. It's only three games from the beginning of the season. We need to show that we are contenders over 10 months.

"We need to improve our performance. That's how I feel.

"We are going to play, on Sunday, again a very good team, a team that is going to fight and is over the moon after three games. If we are not ready and we believe, because we beat Manchester United 3-0, that all is fantastic, I think we are going to crash.

"After you beat Manchester United 3-0 at Old Trafford, a historic victory, it's easy to say it was a fantastic performance and [Man Utd] were not so good. But when you watch the game, it was very thin, the line to be positive or negative.

"In the last three games, we have conceded a lot of chances. Our goalkeeper has made unbelievable saves to keep the team alive.

"We scored and showed character and many positive things, but if we want to fight to be a contender, we have to talk on the pitch. We have to show we are capable after 10 months, not only after three games."

On the prospect of any players leaving Spurs before the European transfer window closes on Friday, Pochettino added: "If it happens, it happens. We are not going to push anyone to leave.

"I am happy with the squad that I have. I'm not going to guess what is going to happen."