THE SPIRIT of Celtic By Numbers has always been 'performance over result' with an abiding mantra of seeking continual improvement.

It is preferential to use European performances as a benchmark rather than SPFL outings, yet Sunday’s derby draw took Celtic a step closer to champions status.

Avoiding defeat to their closest challengers in two 'must-win' scenarios for the Ibrox outfit is gratifying for Ange Postecoglou and co. But there were other, more sobering learnings, to take from this tie.

This isn’t a moaning article (or at least, no more so than usual) but rather one focused on how Celtic can learn and improve for the challenges that lie ahead in the Champions League.

Firstly, a general observation. The positioning after the game that Rangers were somehow proven the best team in Scotland by 'absolutely battering' Celtic is way off the mark. It was a poor game and both sides executed their gameplans poorly.

The initial high press from the away side was effective for about five minutes until the match settled down. After that, Celtic had ample opportunity to play through their press mainly due to the lack of defensive awareness of Ryan Kent and Fashion Sakala as well as Joe Aribo’s reluctance to press the centre-backs too aggressively.

The front three managed only three counter-pressures each according to StatsBomb. Although Sakala led the way with 25 pressures (he played the full 90 minutes) this was way short of the 40-plus Daizen Maeda and Giorgos Giakoumakis had undertaken in winning at Ibrox.

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Celtic passed the ball so poorly in that first half that they did not create the chances the spaces suggested they should. Anthony Ralston, Carl Starfelt and Greg Taylor gave up 22 passes between them. Consequently, the attacking talent was largely starved of possession whilst being able to restrict Rangers to one decent Kent chance.

This weakness in playing out from the back while under pressure - from what was a pretty tepid high press - is one of the glaring areas for improvement on Postecoglou’s to-do list.

Celtic need players in the backline (including the goalkeeper) who are comfortable progressing the ball through the initial press. This needs bravery in pass selection and a sure technique.

You cannot wait for players to be 'free' when facing man-orientated defending. Passing needs to be accurate, often to the foot furthest from the marker and timed for when the recipient is on the half-turn and has a fraction of a second to take the ball under control.

Arguably only Cameron Carter-Vickers of Sunday’s starters is capable of doing that consistently. His passes into the midfield half-spaces for Tom Rogic, Matt O’Riley and Liel Abada have been a feature of the season so far.

A game of two halves then? Well, -ish. Rangers had three areas of pressure and one terrific passing move for the goal amid another mess of a half pocked with poor passing and decision-making by both sides.

Again, those moments were telling in terms of areas for Celtic improvement.

Firstly, the Hoops gave up five, admittedly poor quality, chances from set-piece deliveries. Three James Tavernier corners found Rangers players getting first contact and headers from central to goal. None threatened and all carried an xG of around 0.05. One led to a further shot at goal from Conor Goldson. A further free-kick was met by John Lundstram on 72 minutes which again was headed well over.

Celtic Way:

Celtic have allowed 10.66 xG from set-pieces and corners this season and conceded 16 goals. From shots direct from the set-piece pass, it is 4.6 xG and 10 conceded. The perception is therefore of Celtic being poor at defending set-plays.

While a regression to the mean might be expected here, there is a glaring issue of sheer physicality too. Celtic are a small team. The centre-backs are just over six feet tall and, unless Giakoumakis (6ft 1in) and Nir Bitton (6ft 5in) are on the park, no one else comes close to that. Rogic is tall, at 6ft 2in, but barely jumps off the ground.

Rangers were by far the larger team physically. While this is not advocating for a return to the Martin O’Neill days of half the team standing well over 6ft, there is clearly a height and strength deficit the Hoops need to address as this becomes a bigger issue when combined with better quality opponents.

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In this match as previously, the Light Blues targeted Celtic’s left flank. It is something other SPFL sides do too. Last week, Ross County had some success when Jordan White was beating Starfelt to the ball. The Hoops have three issues on the left side:

1) Starfelt is not notably small for a centre-back (6ft 2in) but gets drawn under the ball trying to win challenges that he cannot. Left-back Taylor, at 5ft 8in, is not very tall

2) Taylor does not possess great recovery speed and, given the attacking nature of Celtic full-backs, is often caught up the pitch on the counter

3) Neither are good passers under pressure – see above

For the chance that brought a great save from Joe Hart, many of these weaknesses were exploited. Indeed, the 'law of three' was in evidence again; do three things wrong in a row and trouble follows.

Celtic Way:

The lack of physicality and speed in the left-back area led to a good chance for Scott Arfield, although it was saved by Hart.

Two minutes later, a couple of misfortunes (Giakoumakis is arguably fouled by Goldson but it is not given, then Callum McGregor miscontrolling the ball) puts Celtic under pressure with Taylor again caught too far forward. Starfelt then makes the wrong decision to be aggressive in closing down Arfield.

Celtic Way:

Celtic got away with both incidents in an otherwise messy half but the point here is that none of these pain points are new. When the Hoops play better quality opposition, like Rangers, the systemic weaknesses don’t stress well and they are left exposed.

It looks like Celtic will be Champions and that is magnificent given where Postecoglou started from.

The Europa League campaign already gave a glimpse of how their defensive frailties do not cope well to the pressure of better-quality opposition.

This latest derby match was a warning - if it were needed - as to the areas Celtic need to improve to ensure competitiveness in the higher European arena.

The good news is the Parkhead club have a perceptive manager who will undoubtedly recognise these things already. Buckle up!