Celtic will take on Romanian outfit CFR Cluj on Thursday morning (AEST) to kick-off the third round of qualifying for this season's UEFA Champions League.
However, 22-year-old Arzani won't be on the plane to Romania with Hoops boss Lennon ruling the young flyer still has some way to go in his recovery from a serious injury.
The former Melbourne City star has been fighting to recover from a serious ACL injury which he suffered last October after coming off the bench for Celtic in his first official match for the club.
Arzani's Socceroos and Celtic teammate Tom Rogic has been named in the squad for the crunch match but he too is doubtful to play.
The mercurial midfielder has been battling knee and ankle injuries during the preseason and has not featured for Celtic since last season.
Lennon said he has been taking a cautious approach with Rogic but believes he could be right to play against Cluj or in their next Scottish Premiership clash against Motherwell on Saturday.
Getting fit might just be the start of Rogic's troubles with the Socceroos star set for a duel with Scottish International Ryan Christie for a spot in the starting line-up.
Christie, in the team to cover for the injured Rogic during Saturday's season opener against St Johnston, scored a hat-trick and was named man of the match after a dominant showing in a 7-0 win.
