Tottenham boss Andre Villas-Boas believes the Premier League this season will be one of the tighest in recent years.
The White Hart Lane outfit was one of the league's busiest teams during the summer, with the likes of Paulinho, Roberto Soldado and Erik Lamela all breaking the club's transfer record as it prepared for the world-record sale of Gareth Bale to Real Madrid.
Tottenham has won four of its first five games this season and hosts rival Chelsea on Saturday, and Villas-Boas says the game will give him an indication of what the club can achieve this term.
"We want to do well against a team that won the European Cup two years ago, won the Europa League that we wanted so much last season. This is the kind of game that you can measure the kind of challenges you might have," Villas-Boas told reporters. "What is happening to us now puts us in a positive mood and we have to collect as many points as possible based on the positive mood we are developing, but it can change very, very quickly.
"At the moment we are on a good run, but there are no clubs on maximum points and this year will be very tight at the top. [Manchester] United are struggling for points, but they have played all the top team at the beginning of the season.
"This will probably become the tightest Premier League in years. It's important for everybody [to win this game]. It would be extremely good to build on our positive start, especially against a good team."
The fixture sees Villas-Boas come up against Jose Mourinho, for whom he worked as a scout and coach at Porto, Chelsea and Inter. He said he enjoyed an "excellent" relationship with the former Real Madrid manager, but had to move on to match his personal goals.
"Our break-up point was because I was full of ambition to give him something extra and I wanted further involvement than the job I was doing at that time, which was scouting and match preparation," Villas-Boas said. "I felt I could give him much more, so my initial idea was to keep on working with him.
"But he didn't feel the need for somebody near to him or in another position as an assistant, and because of that it was decided that it was time, after Inter Milan, to continue our careers [apart]."