xG and me - Leeds United boss Marcelo Bielsa gives his take on expected goals

As November draws to a close, the Whites sit top of the xG table by 13 points, a gap that can only be described as a mile in footballing terms.

Data experts Opta say xG 'measures the quality of a shot based on several variables such as assist type, shot angle and distance from goal, whether it was a headed shot and whether it was defined as a big chance.'

In essence, it is a statistic that measures how many goals Leeds could and perhaps should have scored and, thanks to the dominance they have enjoyed in the vast majority of their games, Leeds should have scored enough goals to win 15 of their 17 Championship games thus far.

According to xG, tonight's hosts Reading should be 23 points behind United.

What the real table, the one based on actual goals and actual victories shows is that Leeds have won 10 times and sit second, two points off the top and 16 ahead of the Royals.

Bielsa has previously spoken of the data and in-depth analysis that helps him form his footballing decisions. Last September he said: "We receive a lot of data. With this kind of data we can build some conclusions and reach ideas. At the end of the day head coaches give value to the data that confirms what we saw during the game."

Since then, thanks largely to social media, a growing appetite for statistical analysis and Leeds' style of football, a style that lends itself to quantifying and produces eye-catching numerical headlines, xG has taken on a life of its own.

If there was a Marmite in the world of footballing statistics, xG would be it. For some, it has merit in the modern day conversation about football, the digital conversation if not the one that takes place in the pub after games. For others it means nothing, ifs and buts too numerous to mention rendering it useless.

But what about the man who has turned Leeds into the xG champions elect?

Bielsa is typically measured in his response, giving his opinion but not as an absolute, neatly summing up the debate but not dismissing either side of the argument. It is the kind of response we have come to expect of the Argentine.

On one hand, he says, the metric holds little value because it has previously suggested an outcome that did not materialise and it cannot be seen as definitive.

On the other, it is yet another signpost that his Whites are heading in the right direction.

"I don't think I have to give value to that," said Bielsa.

"In the last season this kind of statistic showed similar feelings and we didn't get the goal.

"But also I think that when you have positive statistics this is good, it shows you are in a good way.

"I know about this but I also know it is not definitive."