Bayern Munich striker Robert Lewandowski might be the Bundesliga's top scorer, but is he also the league's best finisher? Borussia Dortmund's Jadon Sancho and a number of other players might have a thing or two to say about that if this season's expected goals (xG) metric is anything to go by.
Believe it or not, Sancho is in fact far and away the most clinical player in Germany's top flight this term. His xG rating for this stage of the season puts him on 6.77 goals – that is to say, he was statistically expected to have scored almost seven times in 2019/20.
That is roughly the same as last season, when he had netted eight by the same juncture of the campaign, before hitting four in his last six outings to finish on 12 for the season.
Watch: All of Sancho’s goals and assists in the first half of 2019/20
Confused? Well, xG is a predictive model used to assess every goal-scoring chance and the likelihood of scoring. Such models compute the probability of scoring based on variables such as a player's regular position, the distance and angle to the goal, whether the ball was struck with a foot or head, and whether it came from open play, a direct free-kick, corner kick or counter-attack, for instance.
As an example, a shooting chance from close range from a central position on a counter-attack is more likely to be scored than a header from a tight angle inside a crowded penalty area.
If that is the 'what', what about the 'why'? As complicated as xG sounds, the thinking behind it is simple: to provide a more reliable and sustainable foundation for statistical results than traditional metrics like 'shots taken' or 'efforts on goal', which do not factor in the impact of the above variables.
Watch: The top 10 unexpected goals of 2018/19
All of which brings us back to Sancho. If his initial xG of 6.77 goals is based on past performances and finishing, how come he now has 14 goals and a league-leading xG differential of plus 7.23?
The answer is, simply, individual brilliance. Now 20, Sancho is gaining in experience and physical strength with each passing season, helping him improve on his expected numbers. And to have such a big difference between the two figures underscores his consistently decisive and clinical contributions for Dortmund in 2019/20.
He is far from alone. RB Leipzig striker Timo Werner is second in the chart when it comes to unexpected xG. The Germany international has far surpassed his xG figure of 16.04, having found the target 21 times this season. A positional switch and tactical changes under new coach Julian Nagelsmann, for example, could be factor's in his xG differential of 4.96.
Watch: All of Werner's Hinrunde goals in 2019/20
There are some surprising names on the list, too. Union Berlin forward Marius Bülter is 4.39 goals above his xG with seven, followed by Schalke midfielder Suat Serdar (+4.34 / seven), Augsburg defender Philipp Max (+3.74 / seven), Fortuna Düsseldorf's Rouwen Hennings (+3.68 / 11), Cologne's Jhon Cordoba (+3.56 / 10), Leipzig's Patrik Schick (+3.08 / seven) and Dortmund's Raphael Guerreiro (+2.86 / five).
No Lewandowski in the top 10, you cry? It is not because he is having a bad season: it is simply that with an xG of ???, he was expected to score as many as he has, and had less wiggle room to surpass expectations.