Just found this on a sports lawyers's website: "There are some issues to consider here. Firstly, the 75% rule means that a player must have played in 75% of games of which he has been available for selection. If a player has been injured, this will be taken into consideration when assessing the application and the applicant must provide evidence of the extent and length of the injury and impact on their playing prospects. Suspensions will also be taken into consideration in the same way. To be considered to have ‘played’ in 75% of games, the player needs only to have been selected for the squad."
The only have to be in the squad, not get on the pitch is interesting, also the fact that games missed through injury do not count.