Carlo Ancelotti admits Chelsea will need to maintain impeccably high standards if they are to make an impression in Europe.
The Blues have made the perfect start to their 2009/10 UEFA Champions League campaign, taking maximum points from their opening two games - securing 1-0 victories over Porto and Apoel Nicosia.
The Stamford Bridge outfit can also boast an enviable record in continental competition in recent years, going all the way to the final in 2008.
They will be hoping to go one better than that this time around, but are well aware that they must maintain their current momentum, especially with domestic results wobbling of late, if they are to prevail.
Next up for Ancelotti's men is Spanish outfit Atletico Madrid, a side who have made their worst start to a season in 15 years, and the Italian coach expects another tough test of his side's credentials on Wednesday night.
"We have had difficult games in the Champions League," said Ancelotti.
"Porto, in the first game, was not an easy match because they have very good organisation.
"The same thing against Apoel Nicosia. Everyone thinks that playing in Cyprus is easy, but it's not. Football in Cyprus has improved. For example, the national team won 4-1 against Bulgaria recently.
"There are no easy games. We can play better in the Champions League, for sure, but at the moment it's important to win.
"We want to play our best in March and April when the matches are very, very important.
"Atletico have not started the season well, but they have a very good quality.
"In attack they have Sergio Aguero and Diego Forlan who are dangerous strikers. We have to pay attention to this.
"Aguero has fantastic quality and he can resolve the match with his quality. They're a good team but, at this moment, they haven't found a good disposition tactically on the pitch.
"I think that Atletico has a possibility to return to playing well because they have a lot of quality. Now, at this moment, for them it's not easy because Porto have also made a good start.
"But in these four games, they can still arrive at the top.
"It's a very important game. Not only to get back to winning ways after Aston Villa, but to stay top of the group and move to nine points. This will make the next three games in the group easier."