When Claudio Ranieri was appointed as Leicester manager, many scoffed at the dreadful decision the relegation candidates had made. Now they can win the Premier League by taking three points from three games.

But just how has Claudio Ranieri actually managed to do it? What are the secrets?

A return to 4-4-2

Back in the good old days of young Ryan Giggs, Kevin Keegan: Mr Manager and Blackburn Rovers’ magnificent Premier League win, most if not all teams employed a 4-4-2 formation, with wingers supplying crosses for strikers. That evolved into a 4-3-3, personified best by the Cristiano Ronaldo era United, and then eventually into Jose Mourinho's now all-too-common 4-2-3-1. The cyclical nature of football means we have been due a change for some time and it turns out we're going retro.

Claudio Ranieri is one of several forward (backwards?) thinking Premier League managers to have revived the strike partnership this season. His 4-4-2, like all tactical systems, changes shape during games but is built to suit his players and take advantage of the weaknesses of opponents.