The Wall Justified

The Big Wall is back at Celtic Park and has very quickly reminded us all what we were missing, especially in the crunch games.

In May 19 I wrote The Undisputed Number One where I showed Bain had rightly kept the shirt from Gordon with stellar displays over the end of last season. I then wrote Is Signing Forster Necessary? to add to my list of overly obvious article titles. This showed that both Bain and Gordon had regressed their performances versus the 18/19 season. To answer the question, simply Yes, the big lad was needed.

I was made aware that “Lennon didn’t fancy Bain” quite early in the season. I have wondered what came first: A crisis of confidence from the incumbent picking up on his managers reticence, or a genuine loss of form from Bain?

Either way Forster has re-established his position as Celtic’s premier ‘keeper. As part of the mid term report series, the question is: Does he deserve to do so?

Save %

If I were Sky Sports (I am not) then Save % would be the key stat to use. This shows the % of all on target shots saved.

Bain’s save % last season was very impressive at 85%. The problem is that this takes no account of shot quality. If all the shots you had to save were from 35 yards, you’d expect a high % of saves.

So, we have to bring Expected Goals into it. Hooray.

Saved Shot xG

The below shows the average xG value of shots saved per 90m.

Forster is saving better quality shots than the other two. Gordon’s rate for 19.20 was 0.544 whilst Bain was only saving 0.367 xG value of shots per 90m this season.

Goals Conceded versus Expected

The even more meaningful measure is to consider the xG value of all the shots on target versus the goals conceded.

This illustrates again how well Bain did last season. The shots he faced suggested he should be conceding 0.616 goals per 90m but he only conceded 0.37. With Gordon letting in more goals than the shot quality would suggest it was easy to see why Bain was preferred.

This season Forster is letting in 0.67 goals per 90m but the shot quality he is facing suggests he should be letting in 0.871. So, he is adding value. I am also worried that Celtic seem to be expected to concede more goals! That’s for another day.

This season Bain was expected to concede 1.133 goals per 90m but actually conceded 1.29. An underperformance by that metric. In Gordon’s 6.33 appearances he conceded 0.63 versus an xG of 0.99 which is an improvement for him over 18/19.

Distribution

As I mentioned in the opening mid term report on Lennon, Celtic are more direct and the notion of picking a ‘keeper because of his distribution (e.g. De Vries) is not really a Lennon trait.

Simply, Celtic are not completing anywhere near as many passes and this starts from the back.

Bain achieved 86% pass completion and this season and it is 68% by Forster. The Englishman only completes 48% of Set Piece passes.

Therefore, in the distribution stakes Forster is not an improvement but Lennon probably doesn’t care that much.

Conclusion

Like Jullien, Forster comes alive in the big games. He made 5 saves at home to Lazio, 6 away, 7 at home to Rennes and 8 in the League Cup Final victory where he was Bhoy of the Match. In no other game has he needed to make more than 3.

Forster is an imposing presence, and like Sinclair when Rodgers brought him from Aston Villa, appears to be in the right place at the right time for his career. Long may that continue.