Liverpool’s Big Chances

There has recently been a fantastic addition to the already great Stats Zone app: big chance data. Also sometimes referred to as clear-cut chances, big chances are defined by Opta as:

A situation where a player should reasonably be expected to score usually in a one-on-one scenario or from very close range.

Whilst the much missed EPLIndex site was a great source of the basic big chance data (so whether they were scored or not), using Stats Zone we can now see where on the pitch the chances occurred, and whether or not they were on target. Needless to say, my first thought upon discovering that this information was available was to see how Liverpool have fared at both ends of the pitch in 2013/14.

It’s hugely important to bear in mind that big chances are a subjective statistic. What one Opta data collector may think constitutes “a situation where a player should reasonably be expected to score“, another may not, and so what you think of as a big chance may not have been recorded as such in the stats. When we get to looking at Simon Mignolet’s record later on, you’ll see what I mean.

But first, let’s take a look at where on the pitch Liverpool have allowed and created big chances this season. I have split the centre of the penalty area into three bands, and then I have wide box areas, and outside the box. Penalties are recorded separately, for obvious reasons.

CCC MapSo what can we see here, aside from the fact that Liverpool have had a lot more big chances than their opponents, and converted a higher proportion too?

It’s interesting, if not surprising, that the total conversion percentage by both teams combined drops in the central zone as you move away from the goal: 56% in the six yard box, 44% directly behind that, and then 36% between the penalty spot and the edge of the area. Penalties have been converted at around the league average rate of 80%, with 40% of the wide box opportunities hitting the net.

The only surprisingly high rate comes with chances outside the box (71%) though this is only a very small sample of seven. Looking at the three Liverpool goals, it seems clear that these chances will perhaps often be the results of incisive counter-attacking; the strikes in question were Suárez at Tottenham, and Sturridge at home to Everton and Arsenal.

Similarly, the Reds’ opponents who scored from outside the box were Manchester City (from a counter attack followed by error by Mignolet) and West Bromwich Albion (from a horrific gaffe by Kolo Toure).

In total, Liverpool have had ninety-three big chances and given away thirty-six, meaning they have had 72% of the total clear-cut chances in their matches. However, I recently looked at how the Reds’ shot ratios have varied as the season has gone on, and the same pattern can definitely be seen if we break the big chance data down in to the two halves of the campaign.

In the opening fifteen league games of the season (which goes up to the match with West Ham United at Anfield), Liverpool had thirty-three big chances whilst allowing their opponents twenty-one. This means their big chance ratio for this period was 61%.

However, in the sixteen games since, the tally of big chances is an incredible sixty to fifteen in the Reds’ favour, meaning their ratio is a remarkable 80%. Liverpool are essentially averaging a four-one big chance win per match over the last three months or so.

(As an aside, this figure was sixty to thirteen (an 82% ratio) for the fifteen games prior to last night’s match with Sunderland. The Mackems became the first team to have two more big chances than Liverpool in a league game this season, and so deserve credit for their performance).

As great as these figures all are, I do have one minor concern with regards to this data: the form of Simon Mignolet.

Since saving Yannick Sagbo’s clear-cut chance at the KC Stadium in December, Liverpool’s Belgian stopper has not saved any of the ten big chances that his opponents have put on target. Prior to that, Mignolet had saved eight out of the fourteen he faced in the Reds’ first thirteen games.

Before writing him off though, there have to be a few caveats applied to this fact. The whole point of the big chance statistic is that the attacker is expected to score, and for an attacking move to have reached that point it’s not usually the fault of the goalkeeper.

For instance, if the outfield players make a howler to gift an opponent a golden opportunity (see Toure at West Brom, or Skrtel against Fulham), or give away a penalty (as happened against Arsenal and Swansea) then it hardly seems fair to blame the ‘keeper for a big chance being scored.

The other issue, as hinted at in the introduction, is that this is a subjective stat. Earlier today I tweeted that Mignolet hadn’t saved a big chance since Hull away, and received countless replies suggesting that he had saved big chances from the likes of Rodriguez at Southampton and Rooney at Old Trafford. For what it’s worth, I’d also nominate the save from McAuley’s header at the Hawthorns too.

But to reiterate, these were not deemed to be big chances by the Opta analysts; my analysis has to be dictated to by the data that Stats Zone provide, in order to maintain consistency. Perhaps the issue here is more with the classification of big chances, rather than Simon Mignolet’s ability to save them?

Due to this multitude of caveats, it is, as I said, only a minor concern that Mignolet hasn’t saved a big chance in four months. However, as his Anfield reputation was founded on saving two such opportunities in the final minute of his league debut (the penalty and follow up shot against Stoke), some more big chance saves before the season is out would help to endear him further to the Liverpool faithful.

It is hugely unlikely that the remaining games this season will play out as the reverse fixtures did, but for the record, against their remaining seven opponents Liverpool had twenty-three big chances and allowed only seven. Repeat that, and the Premier League title might just be coming to Anfield for the first time.

Please check out my other articles, and follow me on Twitter, Facebook or LinkedIn. Scroll down to see the related posts for this article. Thanks.

Advertisements

3 thoughts on “Liverpool’s Big Chances

  1. Great post! Hope it works out in the best way possible. No matter what happens, it’s been an amazing season.

  2. Really good blog Beez, one of your very best!

    I just wanted to make a general point on qualitative data though. Qualitative data is extremely important but, as you say, you face challenges in ensuring consistency.

    Data providers live and die by the quality of their data and there are 2 main steps taken to ensure data quality
    1) Training. Every data collector is extensively trained to collect data in the same way and according to the definitions
    2) Data Validation / Quality Assurance. This will include sampling and reviewing of collected data and special case secondary validation for ‘important’ data.

    Sure there will still be some inconsistencies in the final data but they will have been significantly reduced.

  3. Pingback: The Big Three’s Big Chances | Bass Tuned To Red

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s