Ronnie Whelan: Quality gives Arsenal the edge in enthralling title race
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Hard work should come as a default setting for all professional footballers and the top of the Premier League table bears witness to the amount that can be achieved by just doing your job very well.
But class helps too and after a rip-roaring weekend of football, I'm leaning towards the notion that Arsene Wenger holds the strongest cards.
What we are seeing at the top of the Premier League this season is all about hard work, commitment, togetherness and very good coaching.
Leicester City have led the way and still top the table by virtue of all of these qualities and I don't believe that their defeat by Arsenal will derail them from their path at this stage in the season.
They lost some ground, sure, but they were unlucky against Arsenal and for me, the only thing that will really stop them in their tracks is the size of their squad and the impact an injury would have in the next few months.
I now believe that Arsenal have moved into pole position even if they are two behind Leicester. Wenger has almost a full squad to pick from and at exactly the right time in the season.
For many years, these weeks have been a black hole for almost all of Wenger's trophy ambitions but yesterday's win marked something of a milestone and broke a long standing jinx.
The last time the Gunners came from behind in a game they were losing at half-time was back in October 2011, but this time they took advantage of Danny Simpson's sending-off and showed great determination to get the goals they needed.
Spurs did much the same and made a big statement of intent when they beat Manchester City. Like Leicester, this is a squad of players who work, work and then go again if they have to.
I was very, very impressed with the way they rode a wave of pressure from City when Kelechi Iheanacho equalised Harry Kane's penalty and kept playing their football, kept passing and stayed calm.
This is not the Spurs I know. This is a Spurs team which is based on fundamentals and not romance. They do all the things Leicester do just as well and arguably, have more quality - particularly when it comes to the bench.
They had too much energy and fight for City and Manuel Pellegrini looked haunted and hollowed out after the game. Pep Guardiola pulled the rug out from under his feet when he announced that he was leaving Bayern Munich and it was no walk in the park to manage the Etihad dressing room before that happened.
The weekend was awful for both sides of Manchester. City and United were the biggest losers from what was pitched as a hugely significant few days for the title chase and so it proved.
I have no hesitation in ruling them both out of the riunning and that's just not acceptable from two of the biggest clubs in the world and February with two weeks to run
I noticed a couple of stories doing the rounds yesterday suggesting that Manchester United will lose out on Jose Mourinho if they dither for much longer but that would be completely in keeping with the story of the club since Alex Ferguson left.
The confusion we see on the pitch and in van Gaal's eyes is simply a reflection of poor decision-making at the highest level which has delivered the worst squad I've seen at Old Trafford in decades.
I leave Liverpool until last simply because it was a weekend for teams with title aspirations and that can't be said of Anfield.
I think the theme of hard work is still relevant though. Jurgen Klopp has preached that message for his players since he arrived. Often after a spell of graft, you can get a performance like the win over Aston Villa.
With the obvious rider that this is a very poor Aston Villa team, it was still a great performance.
He had an almost smug look on his face during the game and it was easy to see why. The club came through a traumatic week and he handled a delicate situation perfectly.
The ticket issue has been resolved and he managed to avoid falling out with anybody. Add a 6-0 to that and he had good reason to feel pleased.