Arsenal's assault on this season's English Premier League title threatens to be derailed by a chronic lack of pace that afflicts the whole team.
The pedestrian streak in this squad was ruthlessly exposed during the 5-1 annihilation at the hands of Liverpool. Arsenal were static in attack, outrun in midfield and swarmed on in defence.
Manager Arsene Wenger made more than one reference to how pace affected both teams, during his post-match interview with BT Sport, cited by Fifa.com:
It was a very poor day. Only the fans were good for 90 minutes. All the rest on our side, we were poor -- defensively, offensively -- and they (the goals) were all scored in slow-motion.
We were too open. Every acceleration from Liverpool was deadly for us and defensively, from up front to the back, we were not at the level that you are used to.
We have shown since the start of the season we can do that, but of course it raises some questions today (Saturday) because we were caught many times and were a bit naive.
It's not difficult to see how the lack of pace manifests itself in Arsenal's game. In fact, one only needs to look at the performance of record signing Mesut Ozil.
Criticism of the £42.5 million man, once something greeted with disproportionate hostility, is fast becoming common practice. But Ozil's problems, and there are many, are not all due to the player himself.
The main issue is the absence of enough pace around him. It is common to see Ozil receive the ball and immediately look up to scan the field for forward-breaking runners.
But without those runners to aim for, the languid playmaker has to either pass square, or else keep the ball for too long while he waits for some attacking initiative from those around him.
Whenever he does the latter, Ozil is falling victim to a tempo of play that is faster than anything he experienced in either the Bundesliga or La Liga.
Unfortunately, Ozil is surrounded by too many plays of the same type. Santi Cazorla, Jack Wilshere and Mikel Arteta joined him in the middle at Anfield.
They may all ostensibly have different roles in the Arsenal midfield, but all four are essentially the same style of player. They are each methodical, probing playmakers.
That is a fine dynamic when Arsenal own the ball and their creative aces and No. 10s can exploit defensive gaps. But when the Gunners are pushed into chasing the ball, as they were at Anfield, these players are out of their element.
The midfield is shown up as unbalanced because it doesn't feature any athletic runners. That's what Liverpool had and Arsenal didn't.
The former relied on the tireless energy of Jordan Henderson, the tenacity of Steven Gerrard and the direct pace of Coutinho.
The likes of Cazorla and Ozil are never going to track runners, that's just not their natural game. Wilshere is very willing, but his bursts of acceleration come when he is in possession driving forward, rather than hunting the ball across the pitch.
It is also very sad to say it, but Arteta is getting exposed more often. His lack of pace is being targeted by opponents who are simply swamping him with multiple runners.
Southampton did it all game in their 2-2 draw with Arsenal at the end of January. Liverpool also attacked Arteta early and often.
While the mind is still able to anticipate the flow of play, the body is no longer quick enough to react to it. With Arsenal's deepest midfielder found wanting, a lumbering back four is getting exposed.
Arsenal's defence has been outstanding for most of this season. Indeed, if the Gunners win the league it will be thanks to their defensive solidity.
But by the same token, any more collapses like the one at Anfield and against Manchester City in December, will soon eliminate Arsenal from this title race.
Per Mertesacker's lack of pace is well known, but he is not the only leaden-footed member of this back four. Laurent Koscielny was left hopelessly trailing more than once at Anfield.
The French stopper has never been the quickest. Strength, aggression and generally good timing usually hide that weakness.
Left-back Nacho Monreal has not yet found a way to mask how slow he is. It is not just pace that Monreal lacks, but most of his actions on the ball are performed in a laboured way.
When three out of four members of your back four are slow, you are in serious trouble.
Even right-back Bacary Sagna is naturally not as quick as he was. Age and a pair of leg breaks have seen to that.
So the majority of Arsenal's defensive line, along with the man who most often patrols the areas in front of them, are slow. That is far from an ideal combination.
Nor is it ideal to be just as lacking for pace along the forward line. As much as Aaron Ramsey's smart and tireless running are missed in central midfield, Theo Walcott's direct pace up front may be an even bigger loss.
The absence of the extra dimension Walcott provides puts greater pressure on schemers like Cazorla, Ozil and Tomas Rosicky to win this season's title.
Without Walcott, Arsenal are over-reliant on Olivier Giroud, who is never going to stretch a defence. The French target man was abysmal at Anfield.
But his game is about coming short to receive the ball and working short-area combinations with others. It is a compact and intricate method of attack that is often found wanting against top-quality opponents in the biggest games.
The only player Arsenal currently have with the pace they need is Alex Oxlade-Chamberlain. It is no surprise that the young England international was the only Gunner who remotely troubled Liverpool.
He rebounded from a very poor first half to win the penalty that Arteta converted for Arsenal's lone goal.
But as talented as he is, Oxlade-Chamberlain is not yet good enough to make the difference Arsenal will need to win the big games still left in this title race.
Finding a way to manufacture that difference is the biggest challenge Wenger will face this season. The Gunners boss claimed his team were "naive" and "too open" at Anfield.
Solving that problem could involve putting another holding player alongside Arteta. Pairing the veteran Spaniard with currently-suspended Mathieu Flamini hasn't always worked this season. But it could be a necessary tonic during the business end of the campaign.
But answering the problem of a lack of team pace should be Wenger's biggest concern.
Perhaps finding room for Rosicky in the middle could at least help the Gunners move the ball quicker once they have seized possession.
He'll also know that Manchester City will look to do the same at the Emirates Stadium later that month.
If Wenger can't find the right answer to Arsenal's lack of team speed, the Gunners will ultimately be undone in this title race.