Cutting Corners

Celtic had 10 corners against Greenock Morton and there was frustration that despite a few efforts at goal, no tangible reward followed. Can Celtic do more at corners?

Thanks to @MickNolan88 for asking the question on Twitter.

Firstly, here is an article (In the Washington Post!) about the value of corners – https://t.co/ngZZ429iOW. There are different studies on this, but broadly, a goal is scored (either directly from the corner pass, or from the second phase) between 2-3% of the time. So, corners are not the great attacking threat fans think they are when they celebrate the award to their side. That rate of success is equivalent to taking shots from 25-30 yards – think Ntcham’s shooting!

Although it is a “free” cross or pass into the box, the defending side have many players back, and are organised into a defensive shape specifically to deal with the delivery to come. Which is why variety and imagination are needed to break down the defence. This season we have seen Sinclair’s shot against St Johnstone facilitated by clever movement and the blocking off of markers. The movement must be good but so does the delivery, as we will see.

Back to the Greenock Morton game and 10 corners is not the most Celtic have had this season. Top games for corners awarded are:

Overall this season, Celtic’s performance from corners in all matches is:

Of 52 chances (16%), 16 resulted in an effort on target with 6 goals.

Of those 6 goals, 4 were scored directly off the corner kick:

• Ralston v Kilmarnock
• Lustig v Hibernian
• Dembele v PSG
• Boyata v Brechin City

And 2 were from a secondary action following a corner:

• Rogic v The Rangers
• McGregor v Hibernian

Griffiths has assists for 2 of the goals.

Has Celtic performance regressed? Let’s consider data from last season. I only have corner data for SPFL matches, thanks to StrataData.

In SPFL matches, Celtic created 36 chances (again 16% of corners) from which there were 12 efforts on target and 4 goals:

• Dembele v The Rangers
• Boyata v St Johnstone, 25^th January
• Boyata v St Johnstone, 6^th May
• Boyata v Aberdeen

Griffiths again provided 2 assists.

Celtic have actually improved slightly compared to last season.

If we use the Washington Post article as the bench mark, then Celtic are underperforming both in terms of chances created and goals scored.

To dig into the detail a little more, let’s consider both sides of the transaction. Firstly, the corner delivery is key. Awarding 2 points for an assist and 1 for creating a chance, the corner delivery leaders last season were (SPFL games only):

Delivery leaders this season (all matches) are:

Having Armstrong and Griffiths (and Hayes!) out at the same time hinders Celtic’s current corner productivity. Griffiths leads the corner creation count by a distance this season. After him there seems to be a lack of a consistent corner taker. The constant changing of taker cannot be good for consistency of delivery, understanding and practicing of routines at training.

In terms of attempts from corners last season (SPFL only):

Using a system of 2 points for a goal and 1 for an effort on target, Boyata was clearly the most effective target. Sviatchenko had the second most efforts from corners, and obviously he is no longer with us. Only Dembele scored from a corner outside of Boyata in the SPFL.

If we look at this season (all matches):

Although Boyata and Dembele are leading the way once again in terms of efforts and goals, Lustig an Simunovic are at least getting on the end of corners to a greater degree. Ajer, at a reported 6’ 5”, should also prove productive over time.

Conclusion

Celtic are underperforming studies on corner productivity, albeit slightly. The most effective corner takes, Griffiths and Armstrong, are injured currently and Celtic lack consistency of taker. Similarly, Boyata is the most dangerous corner target. He is also injured currently. Ajer may prove an able deputy.

Celtic need greater threat from corners, as well as greater consistency of taker, if overall productivity is to be improved.

Edit 5th March 2018: Dembele scored 2 goals from corners in 16/17, both vs The Rangers. Celtic therefore scored 7 (2.2%). Better but still slightly below average.

This article was written with the aid of StrataData, which is property of Stratagem Technologies. StrataData powers the StrataBet Sports Trading Platform, in addition to StrataBet Premium Recommendations.