Why Rangers captain James Tavernier is the best performer in Scotland

We believe the media's coverage should reflect the professional game’s direction of travel. And with clubs increasingly seeking out the best minds in data to decipher performance and recruitment numbers, it’s only fitting that those commentating also adopt a strong understanding of data in football.

Earlier in the season, we wrote a detailed piece introducing On-Ball Value (OBV), a metric released by the industry-leading data provider, and partner of the Rangers Review, StatsBomb.

According to the company, OBV: “Objectively and quantitatively measures the value of each event on the pitch.”

OBV measures every action that takes place on a football pitch, assessing the change in likelihood of a team scoring or conceding based on individual actions. It tells us the team's most valuable players in different areas, based on the increasing probability of scoring or conceding. 

According to StatsBomb: “We’ve long had expected goals to rate the quality of shots; we now have OBV to rate the quality of aaaaaall the other actions on the pitch in between both boxes.”

Here’s an example from Alex Lowry’s goal against Hearts on the final day of the season.

It is Aaron Ramsey’s pass that provides the assist for Lowry’s strike.

OBV accounts for the value of Adam Devine’s carry and pass to move the ball forward prior to Ramsey’s assist.

The likelihood of a goal was increased by Devine’s actions and as a result, that is reflected in his OBV. The right-back ended the game with his team’s highest Pass OBV at 0.31.

READ MORE: Where do Rangers need to strengthen the most in the summer? - video debate 

Now we’ve refreshed our memory, let’s dive into the numbers which are all taken from the Scottish Premiership. The following categories are used: On-Ball Value, Dribble and Carry On-Ball Value, Shot On-Ball Value, Defensive Action On-Ball Value, Pass On-Ball Value and Goalkeeper On-Ball Value.

To contextualise each category, think: 'Who is the most valuable finisher, the most valuable passer' and so on.

On-Ball Value 

James Tavernier recorded the highest OBV per 90 total at Rangers and in the Scottish Premiership at 0.54. The captain produced another superb individual campaign. Scott Wright and Fashion Sakala are both surprise entries just below.

It’s important to consider the number of substitute appearances the pair have made, which will likely inflate their output somewhat. However, it’s evidence that Sakala’s goals per game ratio and Wright’s direct style in the centre of the pitch make an impact domestically. 

Analysis of OBV’s top 10 rated players league-wide highlights the difficulties of this season. Tavernier tops the list, statistically, he was the most valuable performer per 90 in the Premiership this season.

However, only Wright joins him in the wider contingent; which features six Celtic players. Celtic’s superior chance creation numbers over the season compared to Rangers’ (2.28 to 1.89xG) was the reason behind their superior points total and that is reflected in the number of players high up the OBV list.

Pass On-Ball Value

Tavernier also tops the Pass OBV table, closely followed by Borna Barisic who endured an up and down season while still seeing the quality of his output drop only marginally in an attacking sense, by 0.03. Steven Davis is a more progressive passer than Glen Kamara, John Lundstram and Ryan Jack; as such his higher Pass OBV ranking should come as no surprise.

Also out in front in the league, Tavernier and Barisic are the only Rangers players who make the top 10 in this category, which features a heavy population of full-backs.

Dribble and Carry On-Ball Value

It should come as no surprise that Sakala and Kent top the dribble and carry charts at the club. Kent’s 0.25 per 90 narrowly shades Sakala’s 0.23 total.

Kent has come under criticism for his goals and assists tally. However, as the Rangers Review has discussed previously the winger’s underlying numbers post van Bronckhorst's November arrval, plus his injury lay-off beforehand, offer a different side of the argument.

The duo also stack up favourably in the league-wide comparison.

Defensive Action On-Ball Value

Connor Goldson will be a hard man to replace at Ibrox this summer and his role at the head of the Defensive Action OBV table speaks to his consistency at the back.

Scott Arfield’s position just behind Goldson is left-field. However, given the Canadian averages the third-highest PAdj (possession-adjusted) pressures per 90, this number reveals the importance of his defensive work higher up the pitch.

None of van Bronckhorst’s squad feature in the top 10 league table. This is likely due to irregular activity more than anything with relegated Dundee's Lee Ashcroft boasting the highest score.

READ MORE: Supporting runs and imitating Kyle Walker: Analysing Calvin Bassey's future Rangers role

Shot On-Ball Value

If you’ve been paying close attention to the bottom of the graphs, you may have seen Alfredo Morelos’ name pop up regularly. This shouldn’t cause too much panic. Forward’s OBV averages tend to be lower, Morelos is used to attempting high risk/high reward actions and endured a poor first few months of the season.

However, what these statistics do highlight, along with his above Shot OBV, is the need for consistent goal threats alongside the Colombian in Rangers’ attacking contingent next season. Kemar Roofe’s Shot OBV is by far the highest in the squad, he is unquestionably the best striker of a ball available.

However, Roofe falls behind Kyogo and Giorgos Giakoumakis when the 11 other clubs come into view. This, in a nutshell, proved to be Rangers’ undoing this season. Their best finisher spent just over 1000 minutes on the pitch while Celtic could always rely on one of Kyogo and Giakoumakis.

Goalkeeper On-Ball Value

Buckle up. Last season Jon McLaughlin and Allan McGregor recorded Goalkeeper OBV totals of 0.23 and 0.17 respectively, this season that dropped to -0.02 and -0.08. Last season McGregor saved 5.22 goals above average and this season that number dropped to 0.94.

Rangers were unable to rely on goalkeeping heroics as they did in 2020/21 and as a result conceded goals they simply did not a year before. 

Conclusion 

The above numbers provide a framework for summer recruitment. 

Rangers are well stocked in the ball-carrying department, although a right-winger remains a priority, and possess consistent quality from both full-backs. They desperately require more finishers in the front line and a better goalkeeping performance next season. Next summer, a greater number of Rangers players must populate the top OBV  spots if the league title is to return to Ibrox.