Wing-backs were key to Chelsea’s last title success — and dynamic duo Ben Chilwell and Reece James could be about to bring more silverware to Stamford Bridge.

Thomas Tuchel’s Blues have operated with a back three this term, just as Antonio Conte’s title-winning side set up in the 2016-17 campaign.

And their wide men have hit new heights under the German tactician, racking up ten league goal contributions between them for the table-toppers.

As Chelsea prepare to take on Leicester this afternoon, we take a look at why Chilwell and James are starring this season.

James ups his game

No Premier League defender has been involved in more Premier League goals this season than James’ seven — only fellow England international Trent Alexander-Arnold (five) comes close.

And his figures when it comes to overall creativity are arguably even more impressive. Only Jack Grealish (3.15) and Bruno Fernandes (2.96) have created more chances from open play per 90 minutes than James (2.95).

The versatile 21-year-old is one of a handful of players on four Premier League goals this season but none of the others are defenders. 

Only Mohamed Salah, Jamie Vardy, Michail Antonio, Sadio Mane and Raphinha have found the net on more occasions.

James’ scoring exploits represent an impressive return for a player who had previously registered just one Premier League goal. 

In fact, Chelsea’s No24 has accumulated more than a third of his career total in his last 11 appearances across all competitions.

Chilwell chips in

Chilwell, 24, has scored three goals himself, including the winner as Chelsea narrowly beat Brentford last month.

All of them have come from open play but the former Leicester man has not lost any of his set-piece prowess.

With 0.6 chances created from dead-ball situations per 90, Chilwell ranks fifth among Premier League defenders — one place ahead of Marcos Alonso (0.34), who he has been keeping out of the side.

But the 18-cap England international is also creative from open play, fashioning a commendable average of 1.4 chances per 90 across all situations.

Defender by name only

Speaking after James’ double in the 3-0 win at Newcastle on Matchday 10, Tuchel revealed he does not really see wing-backs as defenders.

He said: "I think this statistic will look a bit different if you interpret the wing-backs more as midfielders, because if you play in a back three it is not really a full-back position, more of a midfield position.

"I would not call them defenders but they have to defend in some moments like defenders. They are more free to attack the box than they are in the role as a full-back.

"So it is necessary that they are included and we bring them to the box at the end of our attacks and increase the goal threat. 

"I am happy when we create chances and I’m happy when we have five or six players in the box to be dangerous."

Rock-solid foundations

As Tuchel says, he likes to pack the penalty area when attacking — but you can only do that with a robust defence and solid midfield structure.

James, Chilwell and Alonso are supported by a rock-solid trio of centre-backs no matter who Tuchel hands a start to.

The experienced Thiago Silva and Antonio Rudiger complement the relative youth of Andreas Christensen or Trevoh Chalobah, resulting in Chelsea conceding a league-low four goals in 11 games.

Throw in the midfield base of Jorginho and N’Golo Kante — possibly the best gap-plugger in the game — and the Blues appear to have a winning formula on their hands.

Strength in depth

While some teams deploying a three-man defence can suffer from a lack of options, Chelsea are well stocked in the wing-back department.

That ability to rotate and rest is just as well, considering the exhausting nature of the role.

Cesar Azpilicueta has started on the right in three of the Chelsea's four Champions League games so far, while Callum Hudson-Odoi — typically a winger — has shown encouraging signs in that position.

With Chilwell and Alonso interchangeable on the left, Tuchel’s system looks set to keep firing on all cylinders this season.