It is highly unlikely that Arsene Wenger was on Jose Mourinho's Christmas card list over the festive period due to their mutual dislike of each other.
But the Chelsea manager might be tempted to send one belatedly after seeing Arsenal stun the Blues' title rivals Manchester City at the Etihad.
Wenger's team played the type of football that Mourinho would generally use in these big games, by ceding possession, defending with discipline and sucker-punching the opposition on the break and at set-pieces.
Indeed, from the way I saw it, it was a rare grown-up performance from the Gunners in these big games. And it should be the template used away from home against the likes of Chelsea, Manchester United and Liverpool rather than a more cavalier style.
As Keith Andrews said on Off The Ball post-match, egos were left aside as Arsenal sacrificed their style to put the result first.
That lack of ego and desire to do the dirty work was epitomised by midfielder Francois Coquelin, who has only got a run in the side after a recent spate of injuries.
Statistically, he was immense. He completed 100 per cent of his tackles, made six interceptions, managed 11 clearances and won 88 per cent of his battles in the air.
This Squawka graphic shows the areas covered by Arsenal's full-backs
Positionally he was also excellent, occupying the space that City playmaker David Silva likes to make his own as he became a big one in the 4-1-4-1 and often he formed a triangle that hemmed in Silva.
The Gunners cause was also aided by the absence of Yaya Toure who is able to break the lines between midfield and attacking zones due to the momentum he can generate on the charge.
Neither Fernandinho nor Fernando can provide that and it meant that Arsenal could mark man for man in the centre without feeling over-stretched by a Toure-type who needs more monitoring.
The full-backs also showed more discipline than usual with Nacho Monreal and Hector Bellerin timing their forward forays more intelligently than is sometimes the case at Arsenal which meant the one-dimensional Jesus Navas and an under-par James Milner were unable to capitalise.
City had 42 crosses, including 16 corners but Sergio Aguero's lack of height made some of that redundant. Additionally, City have scored just two goals from corners all season (compared to 8 for Chelsea), which highlights an area that they need to turn to their advantage more.