The 24-year-old netted a hat-trick for the Bhoys during a 4-1 victory over Kilmarnock on Wednesday night as the Scottish champions came from behind to win.
But Griffiths hasn't had everything all his own way this term, especially at the start of the season - when the forward wasn't starting for Celtic.
To transform his fortunes, Griffiths admits he had to seek out boss Ronny Deila and assistant manager John Collins to find out what they wanted to see from him.
LG: "I had to improve, not playing at the start of the season. Had a talk with manager and John Collins and what they wanted me to do." (MH)— Celtic Football Club (@celticfc) April 15, 2015
LG: "I knuckled down and worked hard and thankfully they are seeing the rewards now." (MH)— Celtic Football Club (@celticfc) April 15, 2015
As for his ambitions for the rest of the season, meanwhile, Griffiths wasn't necessarily happy with his hat-trick against Kilmarnock.
To be precise, the Celtic striker wasn't happy with stopping there, now setting himself the aim of starting every game possible between now and the end of the campaign - and scoring as many goals as he can.
LG: "Only my third hat-trick in football. I just want to start every game from now until end of season and score as many as I can." (MH)— Celtic Football Club (@celticfc) April 15, 2015
With Kilmarnock now overcome, Celtic's next challenge is a huge one: this weekend's Scottish Cup semi-final at Hampden Park, against the side they failed to beat last weekend: Inverness Caledonian Thistle.