So we’ve gone from joint-first to fourth in the space of a few hours after we lost 2-1 at West Brom today, but the biggest blow of the afternoon isn’t the three points we surrendered in my opinion, it’s the injury to Francis Coquelin, if it turns out to be a serious one.

The fact Manchester City were outclassed 4-1 at home by Liverpool means we didn’t lose ground on the team I think remain favourites for the title, but since the summer, my stance has been that to have any chance of winning the league this season, we’d need to keep Coquelin fit, because we simply do not have another player in the squad capable of doing the job he does for the team.

Hopefully we’ll get some good news regarding his knee soon, but looking at the tackle that caused it, the extension of his leg and the jarring impact, it could quite easily be ligament damage. Please don’t let it be as bad as that …

The game itself was one we could have won, but in the end, marginally lost after the hosts responded to Oliver Giroud’s Mesut Ozil-assisted opener after 28 minutes, by scoring twice before the interval to turn the game on it’s head.

In yesterday’s post I wondered if Kieran Gibbs’ goal against Tottenham just before the international break may tempt Arsene Wenger into handing the left-back a starting spot at the expense of Joel Campbell, with Alexis Sanchez swapping wings to the right and Gibbs lining up ahead of Nacho Monreal, but concluded it was unlikely. Yet the boss did just that and to be fair, it worked okay.

Our problems were more defensively on the day, and as much as I appreciate what Mikel Arteta has brought to the club in his time with us, he’s simply not good enough anymore judging by his performances. I think it is telling that he admitted he’d thought long and hard about signing a contract extension because he wasn’t sure he was up to the level required. In the end, he clearly felt he could still offer something but unfortunately for us, that ‘something’ is being a liability.

Although he was unlucky to concede the free-kick that led to the Baggies first goal, getting a toe to the ball as he did, his part in defending the delivery was poor. Giroud was furiously berating his own team-mates as their players wheeled off celebrating and I’m fairly certain Mikel was the target of his anger.

As for West Brom’s second goal, Arteta was in the wrong place at the wrong time, trying to defend the near post but succeeding only in impeding Petr Cech from doing his job and deflecting the ball past his own keeper. That he instinctively tried to stop the ball with his hand was symbolic of a player who’s not just slow of foot, but also of mind, at the moment.

I realise that may sound harsh but when you’re talking title challenges, you’re speaking about fine margins and to be fielding a player so fragrantly not up to the task, both physically and mentally, is madness. Sentiment should have absolutely no place in competition. Hindsight’s 20-20 as they say, but Mathieu Flamini should have replaced Coquelin when he hobbled off after 11 minutes, not Mikel. In all honesty, Flamini’s far from an adequate understudy for Coquelin in my opinion, but he’s infinitely a better bet than the player Arteta is these days.

Santi Cazorla may have salvaged a point for us but did a John Terry and slipped as he tried to convert a late penalty. But we can’t really blame the little Spaniard as it was bad luck, combined with a little unsporting behaviour in trying to put Santi off his spot-kick by the West Brom players, that led to his miss I felt.

Other points to make about the loss include Per Mertesacker’s worrying recent habit of not attempting blocks. I mean, he just stands there at times, refusing to even attempt to close down a shot, assuming, i’m guessing, that he thinks opponents won’t hit the target or that Cech’s better off having a clear sight of of the strike.

Ross Barkley’s deflected effort off of Gabriel’s attempted block at Emirates stadium recently perhaps justifies Per’s reluctance to attempt blocks but I’d prefer we tried to stop shots at source whenever possible. The way Per was manhandled by one of their players for their equaliser was also annoying to see and overall our defending as a unit was poor on the day.

Hector Bellerin looked like a player who’d just returned from injury and wasn’t yet up to match speed and even Laurent Koscielny, our best defender, didn’t play at his best.

Given this was an away match at a difficult ground against organised, resilient opponents straight after an international break and with us still deprived or several players through injury, our performance and the result doesn’t worry me too much.

As I’ve said, it’s the potential long-term absence of Coquelin and if our worst fears are confirmed I think a January signing in that position becomes an absolute must. Identify the player, pay the price and if that means the likes of Arteta, or anyone else for that matter, is pushed down the pecking order to the extent they fail to make match-day squads, then tough luck. We’re trying to win the league, not running a retirement home.

More on Sunday. Til then.