Cesar Azpilicueta's solidity key to Chelsea's consistency in the 2014/15 season
Chelsea have been vulnerable this season only when Nemanja Matic has been absent, but the quiet, unassuming Spaniard Cesar Azpilicueta and his solid performances have been ket to the Londoners run of form and trophy challenge.
When facing this Chelsea team, the aim of opposition managers must be to attempt to highlight any slight weakness of which they can try and take advantage. So far this season, their only defeats have come when Nemanja Matic has been missing or had a rare off day. It isn't at all clear how, therefore, to set about getting one over this year's champions-elect.
One might say that Willian provides less of a threat down the right flank than Eden Hazard, but then he does so much defensive work that that means he isn't really a weakness when it comes to attacking the Blues.
At centre-back, Gary Cahill had a mid-season wobble but looks back to his very best alongside John Terry, while the rest of the team's spine could barely be improved. Left-back provides, on paper at least, their greatest shortcoming.
Last season, manager Jose Mourinho decided that Ashley Cole was no longer the best option available and threw natural right-back Cesar Azpilicueta into that role.
It was thought that the acquisition of Filipe Luis from La Liga winners and Champions League runners-up Atletico Madrid would solve any remaining problems in that position. Azpilicueta has defied the challenges of Chelsea's new left-back and the majority's predictions, though, and made the spot his own. He is certainly no weak link.
He is given very little protection by Eden Hazard, who is quite rightly given the freedom of the pitch work his magic, but opponents rarely get the better of an isolated Azpilicueta.
A right-footer on the left side of defence could often be taken on around the outside, but the Spaniard tends to try and show opponents infield, and when they do make it past him down the line he has a fantastic turn of pace with which to recover.
His 3 tackles per game is amongst the best in the Premier League while he makes even more (3.3) in Champions League matches. All the while he commits just 0.6 fouls per game.
Unassuming in his defensive duties, what makes Azpilicueta so impressive is that his work often goes unnoticed. A full-back's work without the ball is often only highlighted when their opposing winger runs riot, but he is often an unmentioned member of fortified Chelsea performances.
At Wembley last weekend, he starred in a man of the match performance, gaining a rating of 8.52. Andros Townsend, arguably Tottenham's liveliest player for much of the first half, attempted five dribbles that day but completed only two, failing to get a single shot off and remaining largely ineffective.
Azpilicueta made 8 tackles as well as five interceptions and four clearances. Effective in his defending, stronger than he perhaps first appears and extremely powerful, he fits in alongside Cahill, John Terry and Branislav Ivanovic.
What is more, they are a dangerous bunch at the other end, the Chelsea defenders. Between them, they have contributed a whopping 18 goals and 14 assists in all competitions this season, including the Terry cross, flicked on by Cahill and powered home by Ivanovic in the draw at the Parc des Princes.
That goal and many others, have come as a result of a set piece situation when Mourinho throws his big men forwards, and while the player their fans call 'Dave' does not get those opportunities, he still manages to make his own contribution to the attack.
He has three assists to his name this season, the most recent of which set up a winner for Ivanovic at Villa Park. With all three having come from open play, he is one of the Premier League's most effective defenders in this regard, with only four others faring better.
Originally considered an addition to the squad that would be little more than a backup, the £7 million Chelsea paid for his services now looks something of a steal and there is very little reason to think that his place in the team is in question at all anymore.
Since the start of last season, Chelsea have a 72.3% Premier League win rate with Azpilicueta starting, compared to 55.5% when he is missing. He is seventh in WhoScored's rankings in the Chelsea squad, only just behind Ivanovic. They are vastly better off with Dave playing, and he won't be budged from his first team berth any time soon. Rightly so.