Hearts goalkeeper Marian Kello has not been considered for selection of late due to "a private matter", manager Jim Jefferies said.
The 28-year-old Slovakia international has been a key member of the Hearts side which stand on the verge of clinching third place in the Clydesdale Bank Premier League this term but will not be in the squad for Saturday's match with Motherwell.
Kello has also been troubled with a recent back problem, but Jefferies revealed there were other factors behind his recent absence, and he said: "It's a private matter. About a week after he was out after his back spasm there was a report on something which I discussed with Marian and have done two or three times a week (since)."
He added: "When this was brought to our attention I asked him what he thought.
"In the circumstances we decided it would be better if we got it cleared up. Hopefully that will be soon and when it is he'll be back in the team. If that sort of thing is on his mind he wouldn't be in the right frame of mind."
Jefferies declined to reveal the full reasons behind the decision not to select Kello, who last played in the March 19 win over St Mirren.
Jefferies added: "I can't discuss an internal matter because there are legal things involved and it's not right to discuss it."
The Hearts manager dismissed any suggestion that Kello, who has made 29 appearances this term, was not being considered for selection under the instructions of Hearts majority shareholder Vladimir Romanov.
Earlier this season captain Marius Zaliukas was frozen out of the team before signing a new contract.
"It's nothing to do with the Zaliukas situation at all," added Jefferies. "It's something private, internal. It doesn't matter what anybody else says. Marian and I have discussed it and it's a decision we both came to."