Griffiths is amid a three-way battle alongside Celtic stars Moussa Dembele and Odsonne Edouard.
Former Celtic defender Darren O'Dea has told BBC Sport that Leigh Griffiths is not happy when he is forced to watch from the sidelines at Parkhead - and has suggested that one of the club's three strikers could leave.
Brendan Rodgers has brought Odsonne Edouard to the club on a permanent basis from French giants Paris Saint-Germain, after he scored 11 goals in 29 games for the Hoops last term.
It leaves Rodgers with a big headache - Edouard, Griffiths or Dembele up front. The former Liverpool and Swansea City manager is unlikely to change his one-striker system that has worked so well over the past two years.
O'Dea, who currently plays for Scottish Premiership side Dundee and played for the Hoops 60 times, reckons Griffiths is unhappy when he is not playing and reckons Rodgers will struggle to keep all three happy - suggesting one could leave.
"How do you keep them happy?" O'Dea said. "Griffiths, he's matured a lot and he's done well but he ain't happy when he's not playing.
"I know people say, 'Celtic play 60 games'. Well they're not going to be happy playing 20 games each because if they play in the system they have played, which is one through the middle, it's not enough."
The former Wolves and Hibernian striker has scored 98 goals in 183 league and cup appearances for the Scottish champions, even though 61 of those matches have come from the bench.
The 17-time Scotland international has three years remaining on his £18,000-a-week contract (Daily Star) with the Hoops, but has not been short of reported interest during his spell up north.