Celtic midfielder Tom Rogic is injured at the moment.
The Hoops will take on FK Sarajevo away from home in the first leg of their Champions League qualifying first-round tie.
Lennon has said that the 26-year-old Australia international midfielder will not feature in the game due to ankle and knee issues.
Lennon told The Scottish Sun: “Tom picked up an ankle injury in the Scottish Cup final and we knew he would be three to four weeks anyway.
“He could do all his rehab work at home so he didn’t come to Austria. We are hoping that by the time we get back this week Tom will be back on the training ground.”
Blow for Celtic
Rogic is one of the best midfielders in the Scottish Premiership, and his absence against FK Sarajevo will be a blow for Celtic.
The Hoops need to progress to the group stage of the Champions League this season, and the Glasgow giants have to take FK Sarajevo seriously.
Although Celtic will head into the tie as favourites, they cannot be complacent and have to have their best players available.
Title defence
Celtic have won the Scottish Premiership title for the past eight seasons, and Lennon’s side will be favourites to make it nine in a row in 2019-20.
Rangers, though, will give the Hoops a run for their money, with Steven Gerrard’s side determined to win the league title during the 2019-20 campaign.
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