LONDON -- Brentford defender Maxime Colin knew about N'Golo Kante long before the Premier League did. Six years ago the pair were teenagers battling to earn their professional stripes at little Boulogne-sur-Mer, then in Ligue 2, with no clue as to the vastly different trajectories their careers would take as Kante went on to win the title with Leicester before sealing a £30 million move to Chelsea last summer.

Back then it was Colin who was regarded as the more polished prospect, even as the quiet Kante typically aced every running drill.

"At the time the gaffer [Michel Estevan] wanted him to play right-back," Colin told ESPN FC. "I was the first right-back and he was the second one. It wasn't at all his position. He never played -- the gaffer didn't really believe in him."

Colin spent two seasons above Kante in the Boulogne pecking order until the summer of 2012, when the club was relegated to the Championnat National. Everything changed for Kante when new manager Georges Tournay decided that his tireless reserve was a natural fit in central midfield.

"It's really a beautiful story," admitted Colin, who secured a move to Ligue 1 side Troyes within weeks of Kante's positional shift. "In Boulogne, no one expected him to reach this point. But he's really a special guy.

"His best quality is to have the same level [of performance] at every club. He's really humble and never complained about training like a lot of other footballers. He just does his job. He's done really well and I'm really happy for him."

Colin's fondness is clear as he recalls Kante as a shy, unassuming 19-year-old who refused lifts from teammates as he rode a push-along scooter to and from Boulogne training in the days before he could afford a car.

Success has changed things, but not much. A Mini Cooper was Kante's transport of choice at Leicester City and now Chelsea, both easy to miss and utterly conspicuous among the Aston Martins, Range Rovers and BMWs in the Cobham first-team car park. "It's really ideal for him," Colin said with a smile.

Kante took just a season to persuade Caen to give him a chance in Ligue 2, and Colin kept in touch through a shared agent as the two men headed in different directions. Their reunion at Stamford Bridge when Chelsea host Brentford in the FA Cup fourth round on Saturday will be a happy one.

"We have friends in common at Boulogne, so once they knew the draw they all decided to come and see us," Colin said, before adding: "I hope N'Golo will play."

These days managers only leave Kante out if they have bigger priorities, not better options, and Antonio Conte has a Premier League title to win.

Colin's starting spot on Saturday is far more assured. He has established himself as a key contributor at Brentford in the 18 months since his arrival from Anderlecht where, after stepping up from Troyes, he had spent a year competing for minutes with homegrown hero Anthony Vanden Borre.

Maxime Colin has found a home at Brentford after stints with Troyes and Anderlecht. Getty Images

"I really improved a lot in Anderlecht -- I think that was the year I improved the most," he insisted. "For once I wasn't the first right-back. In all my other teams I was always first choice, so it was a change for me to be the second one and push myself to get my shirt."

Colin made 17 league appearances in his only season at Anderlecht and was picked to start the Belgian Cup final ahead of Vanden Borre. He had no intention of leaving until Brentford called in August 2015.

"It was really quick," he explained. "One day my agent spoke to a scout here who said there was a possibility to come. I came here the next day and spoke to everyone, saw the stadium, the training ground and the interest from Brentford was really strong. When a club really wants you like that it's difficult to say no."

Phil Giles, Brentford's co-director of football, further impressed Colin by revealing that the club had identified him after analysing his advanced statistics: balls won, average distance covered and more.

"I was pleased to see that it wasn't just 'We need a right-back and boom, we take Maxime Colin,'" he said. "They knew about me for a long time. The scout I was talking to told me he knew me since Troyes."

Brentford's innovative use of data since Matthew Benham took over the club in 2012 is well documented. As well as the role of advanced analytics in identifying transfer targets, performance feedback from coaches to players takes into account their on-pitch numbers.

Such an approach appeals to Colin, who is more academic-minded than most footballers. He delayed joining a club academy in order to complete school and, even after signing professional terms at Boulogne, continued to study in the afternoon after training sessions.

The plan was to qualify as a physio in case a career in football didn't work out. He only completed one year of his degree before 'Plan A' took off, but has no regrets.

"In football maybe you learn a lot of things, but for life in general it's not good to stay only as a footballer from 14-years-old," he said. "You don't really know real life, and that's why sometimes footballers do stupid things and we all blame them, but we don't know the whole story."

Colin's current contract at Brentford expires in 2019, by which time the deadline to resume his degree in France will have passed. But he is happy and settled in England, even if the relentlessness of Championship football poses challenges.

"I remember in France that when I played three games in one week, it was really a big deal," he said. "Here it's just normal."

Taking on the Premier League leaders on their own pitch will be the toughest test yet. Brentford lost 4-0 on their last FA Cup visit to Stamford Bridge in 2013, but only after forcing the Blues to a replay.

"For us it could also be a win to bring them back to Griffin Park," Colin admits. "It will be a big game for us and it's good for us to test ourselves against the team that is first in the Premier League. I hope we'll do well."

Forcing Chelsea to bring on Kante would be a good sign.