It’s a little over a week after Willian has reached the significant milestone of 300 Chelsea appearances when we sit down with him at Cobham to take stock. The occasion of his triple century, our Champions League fixture in Lille, was made even more special when he volleyed the goal that secured a potentially pivotal European victory.

It’s a little over six years since Willian joined Chelsea. In that time, he’s won two Premier Leagues, a Europa League, an FA Cup and a League Cup, as well as being named our Player of the Year in 2016. He has featured under five different managers and alongside some truly world-class attackers with laudable consistency: 42 games in his first season, then 49, 49, 41, 55 and 56 in each completed campaign since.

‘I always believed I could play so many games,’ says Willian. ‘I had to believe.

‘It’s difficult to achieve this number, especially when you play for a big club like Chelsea because there are many, many players that are fighting for the same position. It was a challenge for me.

‘In football you have to prove yourself every day, in every game. When you stop doing that you have to stop playing. You have to prove it to yourself as well. I have done that. I have been here already for six years, I have had different managers, different players in the squad, and I was proving every training session, every game, that I can play many, many years for this club.

‘I think I have improved a lot. Every game you can learn from. Then after every game you ask yourself "What have I done well, what have I not done well?" I always want to continue improving.

‘Now I’m very proud to reach this number, and I hope for 300 more to come!’

Willian laughs heartily. He knows that won’t be possible, but while he is here he is determined to keep making his mark, just like he did in northern France last week.

We ask Willian if there is anybody he would like to thank for helping him reach this latest landmark, and he instantly reels off a list ranging from Roman Abramovich to the people who work in the kitchen at Cobham. He says the fans have been a source of support throughout, and he also namechecks Jose Mourinho, ‘the coach when I arrived here who gave me the opportunity and trusted me to play for this club'.

As it happens, the two games of his 300 that stand out above the rest to Willian came while Mourinho was in charge.

‘One of them is when we played against PSG in the Champions League,’ he starts.

‘We lost there 3-1, and then the game at Stamford Bridge we won 2-0. Demba Ba scored at the end of the game, and the atmosphere was crazy. I remember every single minute of this game. The first half Hazard got injured, Schurrle came on and scored. We hit the post a couple of times, with Oscar and Schurrle as well. This game was nice because we fought until the end. We believed in ourselves, we believed we could the second goal.

‘The second one was against Everton at the Bridge when I scored in the last minute. That was nice as well! The emotion is different when you win at a game at the end, it’s a release.’

Of course, it has not always been an easy ride for Willian. In October 2016, his mother died after battling a brain tumour. It had a serious impact on his mental and physical health, but with the help of his loved ones and those at the club, he came out of the other end of the tunnel to play a major role in our title triumph that season.

‘That period was very hard for me. It was one of the toughest times for me and my family. Not only after my Mum passed away but before as well: she had treatment, she was fighting, and maybe many people didn’t know about that. They only realised after she passed away.

‘It was tough for me because I couldn’t concentrate well on my work. I would go on the pitch but my head was elsewhere. I lost weight without doing anything. Mentally I had a really tough time, but my family and friends gave me a lot of support, and the people here helped me. It was very nice from them.’

Willian, who turned 31 in August, is just the eighth foreign player to reach 300 Chelsea games. We quiz him on the other seven, pointing out he has worked with them all at some stage.

‘Azpi, Zola, Eden, Didier… Petr Cech…’

He pauses and we provide a clue to help him get the other two, Branislav Ivanovic and John Mikel Obi. He is in exalted company.

‘I have to be proud of that,’ smiles Willian.

‘To achieve this number for this club is unbelievable. It was my dream to come to play for Chelsea. Always I wanted to play for this club.

‘I had this affection with this club since they made an offer for me when I was at Shakhtar. I started watching the games and supporting this team. I loved the name, ‘Chelsea’. The colour blue. And then I had the chance to play at Stamford Bridge for Shakhtar.

‘When I stop playing, my name will be there,’ concludes Willian. ‘No-one can cross it off. I feel proud of that.’

In part two tomorrow, Willian explains what it's like working under Frank Lampard having played alongside him, discusses his current role in the team and outlines his targets for the rest of the campaign...