It completes an excellent past few days for the Blues, with Jose Mourinho's side sealing a second major victory in as many days after beating Manchester City in the Premier League on Sunday.
If that victory said much of Chelsea's title aspirations, their win against London rivals Arsenal was a major statement in their ability to fight on all fronts this term as Mourinho looks to replicate his Stamford Bridge success from his previous tenure.
Fielding a team with 10 changes from Sunday's game—Gary Cahill was the only player to have started for the Blues against City—Mourinho's selection still featured 11 internationals, with the likes of Mata, David Luiz and Michael Essien proving superior.
In contrast, a similarly changed Arsenal line-up from Saturday's away victory over Crystal Palace had little answer for the power of Chelsea, who cruised to a comfortable victory.
It had been an even affair until Azpilicueta opened the scores as Arsenal conceded a counter-attack goal from their own corner.
The Spaniard had never scored for Chelsea, so it was a surprise when he was able to capitalise on Carl Jenkinson's mistake. The Arsenal defender could only watch on as Azpilicueta latched onto his weak header to poke the ball beyond Lukasz Fabianski.
Just over 48 hours earlier, Fernando Torres had done the same to Manchester City, so Mourinho must have been thanking his lucky stars for a repeat against the Gunners.
The Portuguese manager would have been equally happy with Azpilicueta's persistence in chasing what seemed a lost cause, yet more satisfying will be the manner in which Chelsea scored.
Hitting teams on the break is very much a strength of this Chelsea team, and they executed their tactic to perfection, turning defence into attack in a matter of seconds before striking the killer blow.
It was an impressive transition indeed, although Arsene Wenger will be disappointed with how his players reacted to losing possession high up the pitch.
It was a blow they never recovered from either, so when Mata thundered home Chelsea's second, it ended the game as a contest—one that not even the introduction of Mesut Ozil and Olivier Giroud could turn around.
Mourinho has a hold over Wenger—one the Frenchman is unable to escape. He has faced Mourinho nine times, and on each occasion, he has failed to come away with a victory.
To some, this encounter may not have carried the weight or appeal of these teams meeting in Premier League, but it's beside the point. Arsenal have come up short against a major rival again, with another opportunity to lift silverware passing them by.
Chelsea, on the other hand, are looking stronger with each game they play. Right now it seems that whatever starting line-up Mourinho chooses, the Blues have enough about them to overcome the challenge, and that certainly bodes well for the coming months.
At the final whistle, Mourinho made sure he took Ozil's Arsenal shirt. His team took a whole lot more.
Garry Hayes is Bleacher Report's lead Chelsea correspondent and will be following the club from a London base throughout the 2013-14 season. Follow him on Twitter here @garryhayes.