For Arsène Wenger something is not quite adding up. Petr Cech enjoyed the quietest of afternoons in Arsenal's goal yet Steve McClaren and his Newcastle United players were greeted by enthusiastic applause as they strode back onto the pitch and saluted their fans at the end.
The abuse was reserved for referee Andre Marriner and served as a reminder that this was a contest shaped by Alexsandar Mitrovic's early dismissal. That it took a chance deflection off Fabricio Coloccini's leg for Arsenal to ultimately win is partly a reflection of Newcastle's vastly improved commitment, cohesion and tactical intelligence under McClaren but also emphasises that something is not quite clicking for Arsenal. With goalkeeper Tim Krul rarely fully stretched, it was the sort of day when the absent Mesut Özil was missed horribly.
After collecting two yellow cards within two minutes of stepping off the bench in his first couple of appearances for Newcastle United, Mitrovic added a red to his collection. Having started in preference to Papiss Cissé, the Serbia striker lasted 17 minutes before Marriner felt compelled to send him off after a stamp which left Francis Coquelin writhing in agony, clutching his shin. In mitigation, the challenge looked mistimed rather than malicious. But Marriner is unlikely to be the last referee who finds the former Anderlecht striker rather too reckless for his liking.
A little earlier another impulsive moment, from Florian Thauvin should have earned Arsenal a penalty. The French winger, recently arrived from Marseille , got away with tripping Héctor Bellerín inside the area as Newcastle got lucky.
By half-time most neutrals would probably have said McClaren's players deserved their luck. Down to 10 men they worked incredibly hard with Jack Colback and Daryl Janmaat prominent among those doing their utmost to deprive Santi Cazorla, Alexis Sánchez and company the time and space they craved.
It came as a minor shock to realise Theo Walcott, preferred to Olivier Giroud in the lone striker role, and Alex Oxlade-Chamberlain were starting a game together for the first time two in two years. For long stretches they both found themselves forced into a succession of culs-de-sac and blind alleys. Then, early in the second half, Krul parried a Ramsey shot and Oxlade-Chamberlain connected with the rebound. It seemed to be sailing harmlessly wide until the ball took a deflection off Coloccini's outstretched leg and was diverted into the back of the net.