"We have to put the faith in the squad of players that want to be here and want to fight for the result and that's my focus, really - on the players that we have".
'Unfortunately, I could not play because I'm not yet 100 per cent operational, ' the 27-year-old said on Instagram.
But it comes amid increasing uncertainty about his future, with Boyata's agent Jacques Lichtenstein previously claiming the Hoops had broken promises to his client who was the subject of a failed £9m bid. His upturn in form earned him a World Cup call-up for Belgium and he played against England in a group stage fixture in the absence of Vincent Kompany.
Celtic crashed out of the Champions League at the third round of qualifying after a disappointing 3-2 aggregate loss against Greek side AEK and as far as Chris Sutton is concerned, the blame lies with the hierarchy.
Belgian website DH.be quoted the defender as saying: "When I hear I've refused to play since I came back from vacation, it's wrong. The plan is for him to stay here and I don't see that changing".
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It also tied the 36-hole record for all majors, matching Jordan Spieth at the 2015 Masters, Martin Kaymer at the 2014 U.S. Open at Pinehurst No. 2 and Brandt Snedeker (Royal Lytham & St.
'The exams proved I could not play against Hearts and, since then, I'm doing everything I can to be ready as quickly as possible'.
The Belgium worldwide, 27, did not travel with his team-mates to Greece for Tuesday's Champions League qualifier against AEK Athens.
The former Liverpool boss is confident that Boyata will not leave Celtic in the summer transfer window.
"They have done it with so many players - Virgil van Dijk, Victor Wanyama and Stuart Armstrong in the summer - so I would imagine they would sell Dedryck".
Englishman Roberts, 21, spent the past two-and-a-half seasons on loan at Celtic from City.