The French under-21 international has scored eight times in his last six games to take his tally for the season to 20.
How manager Neil Lennon could have done with his prize asset hitting that form earlier in the campaign as Celtic still trail Rangers by 18 points despite four consecutive victories.
Steven Gerrard's men are closing in on ending Celtic's nine-year reign as Scottish champions.
The defensive problems that have blighted Celtic all season were in evidence as St Johnstone took the lead five minutes into the second-half when Shaun Rooney headed home Callum Booth's cross.