Forlan cannot play the Champions League for Inter because he took to the field for Atletico in a Europa League qualifier during the summer. And no one seemed to be aware.
Diego Forlan's absence will be embarrassing for Inter Milan
What do Pippo Inzaghi of AC Milan, Diego Forlan of Inter Milan, and Cristiano Lucarelli of Napoli, have in common?
Inzaghi and Forlan have both been man of the match, and scored two goals in a major European club final. Inzaghi and Lucarelli have both been the Italian top-flight's leading goal-scorer in a season; Forlan has twice won the Golden Shoe, the award for the most prolific marksman in league football across Europe.
All excellent goal-scorers, then. And none of them will be playing with their clubs in the Champions League, at least before Christmas.
The restrictions placed on each club's roster - squads may only contain 25 players - means managers have tricky decisions on whom to leave out.
Milan and Napoli decided they preferred younger support strikers in their arsenal than the veterans Inzaghi, 38, and Lucarelli, 35.
Forlan's absence is a different case.
The 32-year-old Uruguayan was signed by Inter in August, a replacement for Samuel Eto'o, with every right to regard himself as the club's new first-choice goal-scorer.
Yet Forlan is not registered in Inter's Champions League squad as he is cup-tied until the new year because he took to the field for Atletico Madrid in a Europa League qualifier during the summer. "I had no idea that was the case," Forlan said.
Embarrassingly, nor did Inter, whose accountants or lawyers might reasonably be expected to read the rules when they invest millions in a new member of staff.
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