Forster’s A Keeper

On the “A Celtic State of Mind” podcast I discussed whether Celtic should try and sign Forster permanently with Paul John Dykes. You can listen to that here.

The Man of Many Returns

As Paul pointed out, Forster may be the first Celt to sign four times for the club. His reappearance at the end of the Summer transfer window coincided with the newly established keeper Bain injuring his hand. Forster stepped straight in.

Whether by dint of feeling the pressure of an imminent new arrival, or whether a temporary form loss, Bain’s performances had regressed. As I showed in The Undisputed Number One, he had successfully and with merit, wrestled the spot from Gordon from January 2019 on.

Now that Forster is again in control of the jersey, should Celtic pursue his permanent signing (all things being equal)?

Goalkeeping Stats

Comparing Forster 19/20 with Bain and Gordon 18/19 throughout.

I’ll start where the media ends, with Shots on Target Saved.

Bain had a very impressive rate by this crude measure. Crude because it does not account for shot quality.

For this, of course, we need to reflect expected goals (xG) in any analysis.

This tells us the average quality of shots each saved per 90m. Forster’s saves kept out the equivalent of 0.558 xG per game, more than both Bain (0.492) and Gordon (0.442).

Finally, if we look at the shots that went in, we get a sense of the “value add” of the keeper’s saves.

What this shows is that Forster faced shot from chances of the quality that would be expected to yield 0.927 goals per 90m but he actually conceded 0.71 goals per 90m. By saving 0.21 worth of goals over what he would be expected to, Forster is “worth” a goal every five games.

Bain was impressive last season and you can see one of the reasons for Gordon’s demise, that he has started to concede more goals than the chance quality would suggest.

(A footnote: there is an increase in the quality of chance the keeper’s are being exposed to – I’ll dig into that).

Big Game Bhoy

The added bonus with Forster is his performances under the most pressure. You could argue that if Bain got a sense that Lennon was considering bolstering his keeper options, that his loss of form showed a buckling under professional pressure.

Forster seems to thrive under pressure. He is experienced – older than Bain and an England internationalist. His performances against Lazio (5 and 6 saves respectively) and Rennes (7 saves) were integral to European progress.

And in the big domestic Cup games performances don’t get much more dominant than his 8 saves versus The Rangers to secure a fourth League Cup, including a penalty save. To put into context, Forster averages 2.22 saves per 90m.

Finally, he pulled off 4 saves in the Scottish Cup tie against St Johnstone. That sticky 1-0 was one of the hardest of Celtic’s epic cup tie undefeated run.

In those aforementioned 5 cup ties, Celtic could have been expected to concede 8.655 goals but only conceded 3.

To Sign or Not To Sign?

None of us can predict the football economic landscape post the current pandemic crisis. I am writing this from the perspective of current positions, right or wrong.

Forster is ahead of a declining Gordon and a faltering Bain. He is clearly an uptick on both. Even more importantly, my understanding is he wants to be here. His working relationship with coach Steve Woods is excellent, and he feels trusted and valued here.

If he wants it, Celtic want it and Southampton don’t want him I am sure a solution can be found.

I hope so.