A couple of weeks ago I posted a list of the top players in Argentina’s Primera División by expected goals. Let’s look at how the table looks with eight matchdays to go. (There remain a couple of matches to be played in Round 22.)
It’s always beneficial to compare the expected goals of shot events with their actual occurrence on video. After watching highlights of several matches, I realized that most of the shots that resulted from set pieces were not being properly tabulated as such. I made some changes to the code (which has more to do with the quirks of DataFactory match data than the Marcotti database) and verified that almost all of the set-piece related shots are identified. The end result is that there are significant changes in expected goal values for certain players, especially those who make their greatest contributions on set plays.
Here is the list as of the end of Round 22:
The order of this list is a reflection on my decision to include penalty kick events in the xG calculations. In my opinion, these events should count just as much as any other shot event, but I admit that the total xG favors those who take penalties. When xGs due to penalties are disregarded, Diego Vera and Darío Benedetto top the list — neither of whom have penalty-taking duties. Vera tops the list of xG contributors due to his contributions on set-pieces. Benedetto has the highest xG in open play by a wide margin (more than 1.0 xG).
It should also be noted that four players in this list are under 30: Palacios, Driussi, Alario, and Bou.