The 436th CIES Football Observatory Weekly Post presents the rankings of the teams that have trained* the most players active in 48 of the world’s major leagues**. Ajax (86 players trained) is ahead of Benfica (85) and Sporting CP (83), while the Uruguayans of Defensor SC (82 trained) top the table among non-European teams ahead of Boca Juniors (81) and River Plate (79).

Ajax also has the highest score in the weighted training index***, which takes into account the sporting level of the players trained. The Dutch team is ahead of Benfica and Barcelona, with Boca Juniors leading the table for non-European clubs ahead of city rivals River Plate. Two Ukrainian (Dynamo Kyiv and Shakhtar Donetsk) and a Croatian team (Dinamo Zagreb) are in the top 10 positions of the weighted table.

The Weekly Post also presents the rankings for players active in four league sub-categories: the European big-5, with Real Madrid in first place (44 players trained); 31 top divisions of UEFA associations, with Ajax at the top (84); eleven American leagues, with SC Defensor first (70); as well as six Asian leagues, with the Chinese of Shandong Taishan heading the table (37).

* Training clubs are those where players have been for at least three years between the ages of 15 and 21 (including the seasons of the 15th and 21st birthdays).

** Top divisions of the following associations : Argentina, Austria, Belarus, Belgium, Brazil, Bulgaria, Chile, China PR, Colombia, Croatia, Cyprus, Czech Republic, Denmark, Ecuador, England, Finland, France, Germany, Greece, Hungary, Israel, Italy, Japan, Korea Republic, Mexico, Norway, Paraguay, Peru, Poland, Portugal, Qatar, Romania, Russia, Saudi Arabia, Scotland, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, The Netherlands, Turkey, Ukraine, United Arab Emirates, Uruguay, USA and Venezuela.

*** The training index weights the number of players trained per club by their sporting level, calculated according to the capital experience metric. The latter, presented in the Post as a percentage gap from the average observed for all the players in the sample****, combines the playing time of footballers with the average level of matches played in the last year.

**** The sample includes players present on the 1st of October in the first team squad of the clubs analysed. Moreover, they had to have already played in domestic league games during the current season or, this being not the case, to have played matches in adult championships during each of the two previous ones (B-teams not included). The second and eventual third goalkeepers were considered in all cases.