Chelsea reportedly earned an additional £20m payment from Eden Hazard's move to Real Madrid last season, despite the Belgian forward's lack of playing time.
The Blues reluctantly sold Hazard to Madrid in July 2019 for a reported upfront fee of £89m, potentially rising to £150m with various add-ons.
According to The Athletic, one of those bonus clauses was linked to Los Blancos winning the La Liga title in 2019-20 and qualifying for the Champions League.
Zinedine Zidane's side achieved both of those targets, meaning a cash windfall for Chelsea, even though Hazard featured just 22 times in all competitions.
The 30-year-old has not fared any better in his second campaign at the Santiago Bernabeu, either, having been restricted to 15 appearances so far.
However, Hazard has shaken off his latest niggling injury issue to be fit in time for Tuesday's Champions League semi-final first leg with his former side.
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