This week we will find out how good Chelsea really are. Antonio Conte will be satisfied with how things have been going but now they are facing Atletico Madrid and Manchester City in the space of just four days.

Make no mistake about it, these are critical games in the club’s season and provide a huge challenge.

They are coming up against two very strong teams, starting with Atletico Madrid in the Champions League on Wednesday night.

Atletico is one of the hardest places to go in Europe, with the way they play and the atmosphere in the stadium.

On Saturday, it does not get any easier with a home fixture against Manchester City.

Pep Guardiola’s side are in great form, scoring a lot of goals and are three points clear of Chelsea in the Premier League table.

If they win at Stamford Bridge, the gap will be extended to six, which is a fair amount all of a sudden.

However, should Chelsea get through these two fixtures unscathed, then it will send out a real message of intent.

Most of the talk before the Atletico game, though, has been about a player who won’t even be allowed to take part - Diego Costa.

He has agreed to rejoin Atletico Madrid from Chelsea but is not eligible to play for them until January.

It is likely Costa will attend the game but it won’t be a distraction to the Chelsea players.

"The best signing Atletico have made this month is getting Simeone to sign a contract until 2020" Frank Lampard

I know he is well respected by the players and was a popular member of the dressing room.

If he is unveiled on the pitch or is simply there to watch, I’m sure the lads will wish him well and get on with it.

Costa leaving will be a relief to Conte and Chelsea - it is the best thing for all concerned.

If it was just a case of selling a talented striker, then we’d be talking about what a great loss he is to the club. But he had to go. There was no way he could stay at Chelsea, given the events of the summer and the sooner he went, the better.

It’s great for Costa, too. He needs to go and train properly before starting playing again in January. He couldn’t carry on staying in Brazil like he was, it wasn’t helping anybody.

​Atletico have acquired a very good player. But the best signing they have made this month is getting their coach, Diego Simeone, to sign a contract extension until 2020.

There are not many coaches that you can say are as important as the players, but the way Simeone has revolutionised that club since taking over six years ago is massive.

Every year, Atletico are going up against Barcelona and Real Madrid, who have the two best players in the world and more, but they are always challenging for La Liga and in the latter stages of the Champions League.

In Pictures | Stoke City vs Chelsea | 23/09/2017 18 show all In Pictures | Stoke City vs Chelsea | 23/09/2017 1/18 Getty Images 2/18 Getty Images 3/18 Chelsea FC via Getty Images 4/18 Getty Images 5/18 Lindsay Parnaby.AFP/Getty Images 6/18 Getty Images 7/18 Getty Images 8/18 AFP/Getty Images 9/18 Getty Images 10/18 Getty Images 11/18 Getty Images 12/18 Chelsea FC via Getty Images 13/18 Getty Images 14/18 AFP/Getty Images 15/18 AFP/Getty Images 16/18 Getty Images 17/18 Getty Images 18/18 1/18 Getty Images 2/18 Getty Images 3/18 Chelsea FC via Getty Images 4/18 Getty Images 5/18 Lindsay Parnaby.AFP/Getty Images 6/18 Getty Images 7/18 Getty Images 8/18 AFP/Getty Images 9/18 Getty Images 10/18 Getty Images 11/18 Getty Images 12/18 Chelsea FC via Getty Images 13/18 Getty Images 14/18 AFP/Getty Images 15/18 AFP/Getty Images 16/18 Getty Images 17/18 Getty Images 18/18

Atletico are not always the most pleasing on the eye. What I love about them, though, is how Simeone has got them so well organised, how they defend and work as a team.

Atletico have been built in his image. He is a forceful manager.

It will be very difficult for anyone to come in after him and do the job he’s done, so it was hugely important to get him to sign.

In saying that, I would like to see him in the Premier League one day. I like his passion. We have most of the major names in world football, yet Simeone would add to it with his personality and quality.

The player Chelsea have to particularly watch out for tomorrow is Antoine Griezmann. I really like him, he’s such an intelligent player.

Every Antoine Griezmann goal at Euro 2016 6 show all Every Antoine Griezmann goal at Euro 2016 1/6 France 2-0 Albania Antoine Griezmann opens up his account at Euro 2016 with a 90th-minute strike against Albania in the group stages. ANNE-CHRISTINE POUJOULAT/AFP/Getty Images 2/6 France 2-1 Republic of Ireland Griezmann celebrates after equalising against the Republic of Ireland with a header. Getty Images 3/6 France 2-1 Republic of Ireland Dimitri Payet celebrates with the Atletico Madrid man after he scores the winner in Lyon. Getty Images 4/6 France 5-2 Iceland Another game, another goal - this time against Iceland in the quarter-finals. FRANCISCO LEONG/AFP/Getty Images 5/6 Germany 0-2 France Griezmann converts his penalty against Germany in the semi-finals. BORIS HORVAT/AFP/Getty Images 6/6 Germany 0-2 France Griezmann does his trademark goal celebration after scoring France's second against Germany to book Les Bleus' place in the final. PATRIK STOLLARZ/AFP/Getty Images 1/6 France 2-0 Albania Antoine Griezmann opens up his account at Euro 2016 with a 90th-minute strike against Albania in the group stages. ANNE-CHRISTINE POUJOULAT/AFP/Getty Images 2/6 France 2-1 Republic of Ireland Griezmann celebrates after equalising against the Republic of Ireland with a header. Getty Images 3/6 France 2-1 Republic of Ireland Dimitri Payet celebrates with the Atletico Madrid man after he scores the winner in Lyon. Getty Images 4/6 France 5-2 Iceland Another game, another goal - this time against Iceland in the quarter-finals. FRANCISCO LEONG/AFP/Getty Images 5/6 Germany 0-2 France Griezmann converts his penalty against Germany in the semi-finals. BORIS HORVAT/AFP/Getty Images 6/6 Germany 0-2 France Griezmann does his trademark goal celebration after scoring France's second against Germany to book Les Bleus' place in the final. PATRIK STOLLARZ/AFP/Getty Images

Griezmann is not a typical striker as such but still scores a lot of goals. He plays as a false No9 if anything. That makes him hard to pick up.

Every pass is the right pass and he always chooses the tight option. No wonder so many big clubs are prepared to pay silly money for him.

Chelsea should remember they don’t have to win the game. If they come away with a draw they will be happy and it will set them up for the Manchester City match.

I expect Atletico will press high and make it difficult for Chelsea to get up the pitch initially but as the game develops they will want to play on the counter-attack. That suits them.

So Chelsea have to be smart, not come out flying. They need to get some possession and not open up too much.

Still, playing in Europe suits Chelsea’s style anyway. They can sit deep and rely on the pace of Pedro, Willian or Eden Hazard in behind Alvaro Morata to create chances themselves.

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