Ajeti was snapped up by Celtic for £5m from Premier League club West Ham in mid-August and the Swiss international has already featured in three Scottish Premiership matches for the champions.
The striker found his game time limited at the London Stadium and only made nine Premier League appearances for the Hammers last season, over 130 minutes of football.
However Ajeti,who has enjoyed an upturn in fortune in Glasgow as he has already got himself on the scoresheet three times in his new colours, revealed that speaking with Lennon convinced him to sign for the Hoops and potentially breathe life into his stalled career.
Ajeti has once again found his scoring boots in Scotland and the 23-year-old insists that the Celtic boss’ confidence in him rekindled his spirit.
“Everyone knows Celtic and when I signed the main reason was the gaffer”, Ajeti told a press conference.
“I spoke a couple of times with him and he gave me the confidence and made it an easy decision.
“This was one of the main reasons I signed and also another important point was I had to get back to be playing football.
“A striker not playing, there’s nothing worse than that.”
Celtic, who are currently third in the league table, are next in action in the Scottish top flight when they play host to seventh placed St. Mirren on Wednesday.