We at Cartilage Free Captain do transfer rumors often, and we do them well. But sometimes it’s worth doing a deeper dive into Tottenham Hotspur’s transfer targets, what we call Daniel Levy’s Imaginary Shortlist. For this one, we called in some help, because we don’t know that much about Scottish football. We asked the good folks of The Backpass Rule (@thebackpassrule) and Modern Fitba (@modernfitba) to help us get to know Celtic FC LB Kieran Tierney.

The Basics

Name: Kieran Tierney
Age: 20
Team: Celtic FC
Nationality: Scottish
League: SPFL
Primary position: Left-back
Other positions: Can play across the backline. Has played a bunch of right-back for country.

The problem with trying to analyze Scottish players is that it’s nearly impossible to get a read on the league unless you’re watching very closely. If we think analyzing Dutch players is tough, the SFPL is a solid step below the Eredevisie. Celtic, Tierney’s team, is the best of the bunch and still 538 puts them on par with Watford and Bournemouth. The way Tierney gets described in the media, however, suggests he has a chance to be a truly special player. For example:

”Tierney is Scotland’s best player now — he is different to anything else we have got,” Stoke’s Charlie Adam told the Daily Record. “He could play for a Liverpool, Chelsea, Arsenal or Manchester United without a doubt.

I’m not saying Charlie Adam is a good scout, and he omits the best club in London, but it’s high praise for sure. When I first went to look for techno-based clips of Tierney, it was this highlight of Tierney bombing down the pitch to score against second-place Aberdeen jumped out:

Indeed, it reminded me a bit of our old friend Kyle Walker, the quintessential “Pochettino fullback,” going full field to create this goal against Stoke:

Watching Tierney against Bayern in the Champions League, you could see he might be the real deal, getting forward well and staying with Robben. His Champions League tackle, key pass, and dribble numbers looked pretty good too, especially given he was facing PSG and Bayern for 4 of the matches this year. So I reached out to the best (only) Scottish Football Premier League advanced stats site around, The Backpass Rule, to see if Tierney was the real deal (Spoiler alert: yes). Here is our Q&A:

1) Let’s start with the obvious: Where is Tierney’s talent level right now and what’s his ceiling? It can be very hard to tell given the overall level of the SFPL. I’ve seen you post about Celtic’s defense being lockdown on his side of the pitch, but is that because he’s really world class and could play for a Premier League Top 6 team or is it because the right side of Celtic’s defense is porous?

Kieran Tierney has the ability to contribute to a top 6 EPL side now and has the ceiling of being one of the best left backs in Europe. He is 20 but has been the Celtic and Scotland captain in various matches, has held his own against the likes of Manchester City and Bayern Munich and been the first name on the team sheet for a Celtic side that is a cup final away from a double treble.

2) What are the biggest weaknesses in his game right now? Strengths?

Tierney’s ascension to one of the top players in Scotland has come from his strength in both defending and attack. Often, the modern fullback is expected to be an important cog in a team’s attack, of which Tierney definitely is. Often times, fullbacks who are stronger in attack are weaker in their defensive duties (James Tavernier at Rangers being a good example of this). Yet, Tierney is just a strong defending as he is bombing forward in the Celtic attack.

The numbers in the SPFL reflect Tierney’s defensive prowess. Celtic have allowed the fewest Key Passes from the left wing (20), the lowest xG conceded from key passes on the left wing (1.89, the next lowest is Aberdeen at 2.90), the lowest percentage of xG conceded from key passes on the left wing (7.9%, the next lowest is 9.7% and this number is 5 percentage points lower than the league average). He is also 19th in the SPFL in % of successful tackles at 72.1%.

On the attacking side of the ball, his metrics are just as impressive. He is 7th in the SPFL in xA with 6.08 (0.21 per 90). He’s completed the 8th most Key Passes in the SPFL at 44 (1.5 per 90). The average Key Pass he completes has an xA of 0.1373, which is 18th highest in the SPFL. 32 of Tierney’s 44 Key Passes in the league this season have come from an open play pass or low cross, which are more likely to lead to a goal. 43% of his key passes resulted in shots in the Danger Zone, the area of the pitch that leads to more goals. Tierney is able to create good opportunities for his teammates that have a better chance of being scored.

The one weakness Tierney might have to work on is his crossing in the air. His final ball in this situations sometimes lets him down, averaging 0.8 successful crosses per 90 and completing 22% of his crosses, which is 88th in the SPFL.

3) Watching some of his film, his speed jumps as does his ball striking, but going forward he can seem almost overly reliant on pace to beat a man. Does he have the technical skill to take on a man when the competition is better matched to him?

Tierney certainly has speed, as he is one of the fastest players at Celtic and in Scotland. Often times he can glide past Scottish opposition using his superior speed. Yet, he definitely is able to do some things with the ball at his feet.

4) How is the mental side of his game? I’ve seen the broken jaw story and people praising his IQ. Does that come through on the pitch?

He has already appeared as captain for both Celtic and Scotland, so despite being only 20 he is seen as a leader. As you mentioned, in last year’s Scottish Cup final Tierney had his jaw broken by an Aberdeen player’s elbow early in the first half. He had to be taken to the hospital because of it to be treated. As Tom Rogic scored a late winner to earn Celtic the Scottish Cup and a Treble, footage emerged of Tierney running back up the Hampden Park steps to be there with his team. He was among the players to receive the cup and the image of him lifting it towards the Celtic end of Hampden is an image Celtic supporters will not forget.

Much like Harry Kane with Spurs, Kieran Tierney was born and raised a Celtic supporter that came through the Celtic academy. Each time he pulls on the Hoops, it is apparent he will give his all for Celtic. I like to think I am a reasonable when it comes to football. I understood the likes of Virgil Van Dijk were destined for greener pastures. Young French striker Moussa Dembele will be off to a bigger club in the near future as well. Most understand Celtic is a stepping stone in their careers. Yet, it is not unreasonable to think the Tierney will want to stay at Celtic for a few more years, if not for the rest of the career. In the era of badge kissing and not celebrating against your former club, Kieran Tierney genuinely loves Celtic.

5) In ten years, would you think he or Andrew Robertson would have had the higher peaks?

The irony of Scotland having two world class players at once who play the same position is not lost on most. Robertson has burst onto the scene (and as every commentator that is calling a Liverpool match is happy to tell you, he was at League One Club Queens Park only years ago) lately with Liverpool. The 24 year old full-back is entering the prime of his career and deserves to be starting in a Champions League final.

I would put the two at about an even playing field ability wise, though willing to listen to arguments either way. The one thing Kieran Tierney has ahead of Robertson is his age. It is worth repeating that he is only 20, turning 21 in June! In the age curve, he has yet to hit his peak years and will only improve. He has had experience playing international matches, Champions League matches, and has won silverware already. This type of experience for a 20 year old is invaluable and you could surmise he will only improve at his age.

6) Celtic got chopped up by PSG and Bayern in three of the four matches in Champions League. How much of that was on Tierney and did he look like he belonged in those matches? No shame in getting beaten by the likes of Neymar and Mbappe of course!

Both PSG matches this season were ugly, as well as the match in Germany. I think Brendan Rodgers has to take some of the blame on how those matches against the Parisians went, refusing to budge from his principals in playing attacking football. However, Celtic more than held their own in the match against the Bavarians at Celtic Park giving up the losing goal in the last quarter of the match despite playing well most of the match. Tierney accounted himself well against Bayern in that match, to add to his fine performances against the likes of Man City and Borussia Monchengladbach the year before in the Champions League. His play in both the group stages and qualifying stages for Celtic shows he can thrive at that level.

The Verdict

Likely price: £25 Million

Chances that the valuation is wrong: Who knows? He’s young and potentially very good. But if Kyle Walker is just £45-50 then half the price seems reasonable.

Team’s willingness to sell: Unclear. As above, Tierney might be a Celtic lifer. He seems to bleed for the shirt and the club know it. On the other hand, he’d fetch a good amount of money and moving

Fit at Tottenham Hotspur: If his talents translate, he’d be a perfect fit at Spurs. Spurs are in desperate need of pace out of their fullbacks again and young, two-way players in that roll. He has played against the best teams in the world and in front of massive passionate crowds in Glasgow.

Possibility he ends up at Spurs: Who knows?! It is early yet, but Spurs are definitely in the market for a new left back, and a young, tough player seems like a Pochettino/Levy special.

Grade if this transfer goes through: A-.