Chelsea star Cesar Azpilicueta's move and success at left-back has been one nobody saw coming, barring Jose Mourinho.
The Spaniard had struggled to displace Branislav Ivanovic at right-back since arrival, and has grasped his opportunity on the left with both hands.
The victim at Chelsea of his superb form has been Ashley Cole, displaced by the 24-year-old, but his progression is having an impact for his country too.
Azpilicueta was picked as a starter by Vicente Del Bosque in last week's 1-0 win over Italy, in the absence of Barcelona star Jordi Alba, missing through injury.
It was a role Arsenal's Nacho Monreal would have expected, or at least hoped, to be handed. It was he who started the crucial World Cup qualifier in Paris against France, providing an assist as they gained an important result.
Yet Azpilicueta's emergence means that along with Alba, Monreal could end up missing out on the Spanish squad altogether at the World Cup, a tournament he helped his nation reach.
So just why and how has the Chelsea man usurped Monreal in the pecking order? Here is a look at three areas of their Premier League performances.
|Player||Team||Pos||Total Att Assist / apps||Goal Assist / apps||Goals / apps||Apps||Mins|
Defensive stats part one
|Player||Team||Pos||Aerial Won / apps||Interception Won / apps||Won Tackle / apps||Apps||Mins|
Defensive stats part two
|Player||Team||Pos||Outfielder Block / apps||Effective Blocked Cross / apps||Effective Clearance / apps||Apps||Mins|
Looking at the above, it's clear to see where the Chelsea man has a clear advantage over his more experienced compatriot.
While Monreal is more accomplished going forward, it's of little substance and end product to his Gunners side. Far more emphatic is Azpilicueta's defensive contribution for Chelsea.
Azpilicueta, a signing from Marseille betters Monreal in six key areas; shots blocked, crosses blocked, clearances, interceptions, tackles, and aerial duels. In some case his per game average is more than double the Arsenal.
Whether Vicente del Bosque takes these statistics into account could be interesting, or whether he simply uses his eyes and likes what he sees.
Azpilicueta is already holding down a regular place from England's number one left-back in recent years, while Monreal can't consistently displace Kieran Gibbs, a player below Cole in the Three Lions pecking order who can't get a look in.
At this point it would be a major shock if Azpilicueta did not go to the World Cup, his versatility to play right-back also key. Looking at the above, it's hard to argue he does not deserve the call-up.