Moses Crucial For Chelsea  (Sky Sports)

Victor Moses has finally found his role. Find out why he has been so important to Chelsea.

Mario Melchiot recently recalled a conversation from his playing days. The former Chelsea defender was speaking to Roberto Martinez, his then manager at Wigan Athletic, about a team-mate. "We talked about how we couldn't believe no big club could see it," Melchiot explained. The man in question was a teenager called Victor Moses.

A couple of years later and Chelsea did spot something. However, Moses nevertheless spent the past three seasons on loan elsewhere. "The toughest time was pre-season, when you know that you've done well and the manager has never spoken to you," he admitted.

On Monday, Moses finds himself up against West Ham, the club where he spent last season. It was a campaign in which hopes of Moses' huge potential began to fade. After all, he was an unused substitute more times than he completed 90 minutes for Slaven Bilic's side.

And yet, here we are with Chelsea clear at the top of the Premier League table and Moses having played his part in that success. In fact, the 26-year-old Nigeria international can lay claim to being a pivotal figure in Chelsea's turnaround under Antonio Conte.

Diego Costa is the top scorer, Eden Hazard the star man and N'Golo Kante surely the signing of the summer. But all three were playing as Chelsea claimed just one point from three games in September. It was the introduction of Moses and the switch to 3-4-3 that changed things.

In hindsight, the move can appear obvious. Hazard is enjoying greater freedom and Kante's ability to play in a two-man midfield is being exploited to great effect. But there was nothing inevitable about entrusting the right wing-back role to Moses. No clamour for his inclusion.

And yet, the player has been a revelation, adding the sort of thrust from deep that was lacking during Branislav Ivanovic's final days at Stamford Bridge. Moses is no full-back forced into an advanced role. Instead he is a genuine threat.

As Conte puts it, Moses's presence in the role provides "the opportunity to exploit one-v-one" and he has taken that chance emphatically, completing the most dribbles of any full-back or wing-back in the country so far this season.

Indeed, only Hazard and Costa have beaten a player more times than Moses at Chelsea this year - his 44 dribbles dwarfing the tally of 13 by Marcos Alonso on the opposite flank. It underlines the fact that Chelsea's system is not simply symmetry. The roles are different.

For while Hazard's trickery is a key feature of the team's attacking play down the left, the combination play has been the story on the right flank. Perhaps surprisingly given Hazard's brilliance, many of their goals have come from moves on the opposite wing.

Pedro, for example, has been directly involved in 10 goals in Chelsea's last nine games, enjoying the benefits of the space afforded by Moses's forward runs. They are not to be underestimated. "Wing-back isn't an easy position to play," explained Melchiot.

"Of course it asks for a lot of fitness, but also intelligence because you need to be on time, helping out the defence, but when the team goes forward you need to be there to give them the outside option and even take people on to deliver a cross into the box."

He has completed more crosses from open play than any other Chelsea player and with such pace and power, Moses is suited to coming onto the ball deeper rather than collecting the ball with his back to goal. "He looks perfect for the system," says Jamie Carragher.

Of course, the change of position has been particularly challenging from a defensive point of view and there is still a suggestion that it remains an area that Chelsea's opponents can look to exploit. But Moses is improving and he has actually been dribbled past less than Alonso.

It helps that Conte is on the case. "He is constantly in my ears just to make sure I'm doing the right thing and in the right position," said Moses recently. But the coach has been sufficiently impressed for the player to be rewarded with a long-term deal.

A new contract. A new dimension. After a length wait, Moses has emerged as a key man in the country's best team in a position in which few had expected him to flourish. As such, he goes back to West Ham as Conte's most unexpected, and perhaps most important, triumph.