1. Arsenal fans have developed a particular enmity for Manchester City

The Manchester City "feeder club" tag was never going to make Gunners enthusiasts warm to the cash-soaked league leaders and with rumours that Robin van Persie could join the exodus north next summer, to play alongside Samir Nasri, Gaël Clichy and Kolo Touré, the bitterness is not about to cease.

The Emirates Stadium can be as quiet as the Highbury Library on occasion, but on Tuesday night it was rocking as the home congregation jeered and sang songs directed at Nasri and took any chance to mock their opposite numbers. The time-honoured "Who are you?" was sung back and forth: the answer Arsenal fans fear most is that City are the club who come calling each year to take yet another star. On this evening, the home fans were also forced to swallow being beaten.

2. Owen Hargreaves is on a long road back

The former Manchester United and England midfielder was making his third appearance for City, following a prolonged injury nightmare. He requires game time but on this showing it will not be easy for him. A misplaced header after 25 minutes was about all he mustered during the opening exchanges, as he sat in the holding midfield berth. As half-time approached the 30-year-old's radar was again askew as a slipped pass beyond the Arsenal defence found space but not a colleague.

Frustration spilled over when he was booked on 58 minutes, for dumping Emmanuel Frimpong to the floor, but after that there was the odd flicker of the operator who has shaped games for United, Bayern Munich and England: one quick look up before dinking a reverse ball into Edin Dzeko was about as good as he got. At least he survived 79 minutes before leaving the field, apparently unscathed.

3. Alex Oxlade-Chamberlain may have the muscle Theo Walcott lacks

The No15 shone brightest for Arsenal. Early on, he caused the experienced Pablo Zabaleta problems, forcing a corner with a left-foot effort and fashioning a give-and-go with Marouane Chamakh that ended with a shot that Costel Pantilimon had to save sharply. Stefan Savic was the next opponent he terrorised when, after applying the after-burners down his right flank, he turned a nothing ball into a 50-50.

After the break, Oxlade-Chamberlain resumed. A ducking, weaving run finished with him unloading with his left again – Pantilimon punched away. A later attempt on goal was just a little too high. In this company the 18-year-old was at ease, and unlike Walcott when he joined the club – also from Southampton – Oxlade-Chamberlain has the muscles and build for the hurly-burly of the elite game. Whether Wenger gives him a prolonged chance at that level remains to be seen.

4. Costel Pantilimon could be an able deputy for Joe Hart

The 24-year-old Romanian suggested he may be able to handle the step up, if required. His first save was a stunning reflex effort from Park Chu-young at close range – the 6ft 8in keeper threw out a paw to parry. After 27 minutes a fine save tipped away a fierce 25-yard shot from Oxlade-Chamberlain. And although the Romanian international missed a chance of glory at the close, when failing to kick at Lukasz Fabianski's empty goal after the Arsenal goalkeeper had wandered up for a corner, this was an encouraging outing.

5. Arsenal and City should stop complaining about fixture congestion

At this time of the season a familiar cry can be heard, bewailing how the Carling Cup exhausts players and generally gets in the way of what really matters – the Premier League. Arsène Wenger and Roberto Mancini were both at it before this tie. City may have had only two days rest after their draw at Liverpool but Mancini could still field an XI worth north of £120m which featured Nigel de Jong (a World Cup finalist), Adam Johnson (an England winger) and Kolo Touré (an Arsenal Invincible).

Wenger's grumbles were backed up by his captain, Van Persie, who wrote in the programme: "I know it's hard to get fixtures right for every single team but I don't really understand the scheduling either for us or City." Arsenal had an extra day to recover.

Maybe they should all just stop moaning and get on with it.