Graham Potter is slightly taken aback when told that it is now more than five months since he took charge at Chelsea as he reflects on the lessons he has learned in that time. 

"It feels longer than that," replied the 47-year-old. "Five very challenging months I would say. I've learnt a lot about the club, a lot about the people here, all the staff at Cobham. 

"It's been a really fascinating period. You've also got the unique situation of the World Cup and the condensed fixtures and then how to deal with the injuries that we’ve had as well in the season, and also managing a club of Chelsea's size and expectation, learning about the extra media scrutiny and all the noise that inevitably comes with a head coach role at a club like this."


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After a very positive initial spell that featured Champions League wins home and away against Milan, along with league victories against Crystal Palace, Wolves and Aston Villa, things started to take a turn with a goalless draw at west London rivals Brentford and the blow of a late equaliser conceded at home to Manchester United. 

While progress in Europe continued serenely, domestic form continued to dip, with an exit from the Carabao Cup at Manchester City's hands coming amid a spell that saw Chelsea capitulate at the home of Potter's old side Brighton, as well as come off second best against Arsenal and Newcastle.

Hope of a post-World Cup revival briefly reared its head following a 2-0 triumph over Bournemouth, only to be followed by dropped points at Nottingham Forest and league defeats against City and Fulham, while another false dawn against Crystal Palace preceded draws to Liverpool and Marco Silva's men. 

Add into that mix a 4-0 thumping at the Etihad in the FA Cup and it's easy to see why the Blues faithful would be despondent as their team sit ninth, but there is a ray of light in the form of the returning Joao Felix, who is set to start at relegation-threatened West Ham on Saturday lunchtime - in a game you can watch exclusively live on BT Sport

Felix was the standout player for much of the first half during his Chelsea debut at Craven Cottage as he started alongside Kai Havertz, with his elusive movement and effective link-up in a variety of areas on the pitch causing problems. 

However, a reckless challenge on Kenny Tete saw him given his marching orders on 59 minutes, a red card that sidelined him for three games. 

The remainder of that SW6 derby and all the fixtures since have illustrated just how much less of a threat the team look without the 23-year-old, as Potter outlined what he considers to be the Portuguese magician's best position. 

"He had a really positive 60 minutes for us. Obviously the red card is a blow for us and a blow for him because he's here to play and play far more often [than he was at Atletico Madrid] and then he gets a three-game ban.

"Sometimes you can get through those three games in a week, but it seems that this [ban] has dragged on quite long because of how the fixtures have gone.

"He was disappointed of course, but as the time's got closer and closer, you can see that he's more and more itching to play, more and more showing his qualities again. We're really looking forward to seeing him on the pitch. We need to decide what role he plays, but he's a fantastic player. 

"Generally I think [playing him] centrally gives him the option to move both sides, which I think is favourable for him. He's got the quality that can play central, left or right – it just depends on the rest of the team.

"[He's] really good at finding space, whether that's to feet or in behind [and] he can challenge the backline as well as he can receive in tight areas, so he's got a unique set of skills. Our job now is to get him on the pitch to do a lot of the stuff that he does well and enjoy his football."

Reece James and Ben Chilwell pose for a photo during a warm-weather training session in Abu Dhabi in December

Continuing with the theme of returning players, Reece James, Ben Chilwell and Raheem Sterling all enjoyed action off the bench against Fulham last Friday (although Sterling is doubtful for the trip to the London Stadium having picked up a knock in training during the week). 

Given their importance to the team's style of play - particularly James and Chilwell - there could be a temptation to rush them back into a starting role as Chelsea look to claw their way back into top-seven contention, but Potter knows that the balance of testing their limits is a tough one to strike. 

"That's our next challenge almost," Potter said on the task of getting the trio fit to play 90 minutes. 

"[It's] good for us that Reece had 60 or so minutes against Fulham. Ben's a little bit behind that but is still available for us, and Raheem got slightly less than Reece but more than Ben, but obviously the knock has set him back a week or so I would guess at this stage. That's the next bit of our challenge: how do we get them all up to speed [and] all ready to play Premier League football?".

The player who's had the biggest impact in the last few weeks though has arguably been Benoit Badiashile, who arrived last month from Monaco amid the glut of big-money signings and has slotted in seamlessly alongside Thiago Silva, helping to keep three successive clean sheets. 

At around £33m, Badiashile's acquisition could well prove an absolute bargain, with the centre-back on a mammoth seven-and-a-half-year deal. 

Benoit Badiashile makes a pass against Fulham

"We're really happy with him and how he's settled in," Potter said.

"He's got a nice partnership with Thiago [Silva]. He gives us balance in terms of a left-footed centre-back and his range of pass, his passing calmness and his decision-making are really good. He's still learning – he's not the finished article. That's exciting for us.

"He's already shown a really good level. Our job is to just keep helping him improve so that he can make the most of his quality, because he's got all the attributes that you need to be a top, top defender."

The influence of the imperious 38-year-old Silva has also eased the transition for his young defensive colleague. 

"I think Silva has helped him. Thiago's a fantastic player and where he's at this stage of his career, his job is of course to help others, but at the same time he also needs to focus on himself.

"He needs to perform at a good level so that he carries on playing and can bring himself into the game in the best way, but he's found a nice balance.

"It isn't straightforward to do, but he's done it really well and he's undoubtedly helped Benoit and Benoit's helped him as well, so it’s a nice partnership."

Graham Potter punches the air after Brighton's 2-0 win at West Ham in August

Perhaps encouragingly for Chelsea, Potter enjoyed an unbeaten record against West Ham in the seven games he faced them as Brighton head coach, the last of which was a 2-0 win at the London Stadium in August. 

West Ham are currently experiencing a mini-revival however, having beaten Everton and drawn at Newcastle to arrest an awful run that had seen them pick up just one point from a possible 24. 

Having previously denied that his impressive head-to-head record holds any relevance going into this latest meeting, what does Potter feel is the difference between August and now in terms of the opponent he will face?

"The difference for us is the fact that we're Chelsea - it's a London derby. The atmosphere is different when West Ham play Chelsea than it is when West Ham play Brighton. That's the big factor. 

"They've always been a strong side. David Moyes' teams are always well organised, have a fantastic understanding of what they're trying to do, [are] defensively very good but can also attack big spaces [and are] strong at set-pieces.

"We have to earn the right to win and we have to match the intensity that's going to come our way."

The stage is set for a tasty London derby. 

Watch West Ham vs Chelsea live on BT Sport 1 and BT Sport Ultimate from 11.30am on Saturday 11 February.