Hearts owner Vladimir Romanov removed captain Marius Zaliukas from the team to play Rangers on Saturday to avoid him being sent off again by Iain Brines, it is understood.
Zaliukas was in the plans of manager Jim Jefferies until the morning of the game, when he was apparently told not to play the defender.
Jefferies refused to divulge details when quizzed on the subject after Saturday's 4-0 Clydesdale Bank Premier League defeat, responding: "He wasn't available for selection - that's as much as I'm going to say on it."
But it is believed that Romanov acted because match referee Brines had sent off Zaliukas on two previous occasions.
Brines most recently sent off the Lithuanian in a 2-2 draw at Easter Road last month, showing him a straight red card for a penalty-box foul on Hibernian striker Akpo Sodje.
Zaliukas was previously dismissed by Brines in controversial circumstances in a 1-0 defeat at Aberdeen in December 2008.
Hearts later appealed against the decision but it was turned down by Brines himself, who ruled that the centre-back had headbutted Dons striker Lee Miller.
The club announced they were "dismayed" by the decision at the time, which they termed a "complete injustice".
Source: PA
