To hear Leigh Griffiths tell it, the intervention staged by Celtic boss Ronny Deila and assistant John Collins was definitely closer to a kick in the what-nots than it was a pat on the back. Whatever the detail of the conversation, and however lasting the effects may be, the short-term impact on the 24-year-old force of nature — often as unruly and unpredictable as a whirlwind — has been nothing short of remarkable. As the kid himself puts it: ‘Being top scorer now means that, since I have had a talk with the manager, I have knuckled down and proved him wrong, proved JC wrong and shown that I deserve to be here.’ Hat-trick hero Leigh Griffiths with signed match ball and man of the match award . Rather revealing, isn’t it? Clearly demanding Deila and original gym rat Collins did not hold back in dealing with the gifted but wild natural talent, wielding a big stick in a bid to persuade Griffiths that the carrot wasn’t such a bad alternative to chips and tea cakes. ‘I had to improve,’ admits the former Hibs star. ‘I wasn’t playing at the start of the season. I had a talk with the manager and John Collins about everything and about what they wanted me to do. ‘Thankfully, in the two months since the turn of the year, I have knuckled down and they are seeing the rewards now. ‘What did they say to me? I had to be working hard in the gym and working hard to get my fitness levels up. I did that and I have been bang on form since the turn of the year. ‘When I was at Hibs, I would have been the first name on the team sheet given the goals I scored. ‘But coming here, it’s a massive club and, with the new manager coming into the club, he wanted to impose his own philosophy. ‘Playing one up front, you have to work hard and my fitness levels were not up to his standards. Since January, though, my fitness levels have been good and I have been scoring goals. ‘I was brought to Celtic to score goals and I’ve started to do that since the turn of the year. I haven’t set any new targets — but I do want a good run of games. ‘I want to be starting every game from now until the end of the season and score as many goals as I possibly can. Celtic's Leigh Griffiths (right) completes his hat-trick against Kilmarnock . ‘The manager selects the team he thinks is best to win the game and we have boys in the squad and coming on from the bench. ‘Myself, Anthony Stokes, Stuart Armstrong, Gary Mackay-Steven were all on the bench against Kilmarnock.’ Griffiths is making a stronger case than most by banging in the goals, his hat-trick in Wednesday night’s 4-1 home win over Kilmarnock definitely ranking among the better substitute performances the Scottish game has seen this season. His second treble haul in Celtic colours took his total for the season to 15 goals, the majority of those coming in 2015, as he has contended more frequently with John Guidetti, Stefan Scepovic and Anthony Stokes for the lone striker’s role favoured — for now, at least — by Deila. Watching Guidetti amble around aimlessly until Griffiths arrived to partner the big Swede on Wednesday night, it definitely seems as though Deila has only two options for Sunday’s Scottish Cup semi-final against Inverness. Either he plays both in a traditional front-pairing. Or he lets Griffiths, scorer of an early opener against Caley Thistle in the Highlands last weekend, loose on his own at Hampden. If his midweek goals explosion makes it impossible to omit the former Livingston, Dundee and Wolves striker from the starting XI, his record in major semi-finals at the national stadium also counts in his favour. Substitute Griffiths came off the bench to spark Celtic into life after lacklustre first-half . The extra-time hero as he scored his second of the game to ease Hibs past Falkirk 4-3 at this stage of the Scottish Cup two years ago, Griffiths also opened the scoring for Celtic against Rangers in the League Cup semi earlier this season. ‘I’ve played in two semi-finals at Hampden and I have won two,’ he points out. ‘Hopefully, I can continue that. ‘I’ll be looking to score again. But the most important thing is for the team to win the game and reach the Scottish Cup Final. ‘Inverness will come down and make it difficult for us. They proved last weekend they are a hard team to beat. ‘Every game against them this season has been tight and I expect the same again on Sunday.’ If Griffiths starts and plays as he did against Killie, even Caley Thistle at their most obdurate will struggle to cope. His hat-trick — one perfectly placed header, one absolute screamer from distance and a driven low finish — was a timely reminder of what he can do, when the mood is upon him. Celtic manager Ronny Deila (left) congratulates Griffiths after the final whistle . ‘It wasn’t a bad night’s work,’ he says with a smile. ‘It was just good to get the win because we were disappointed not to win at Inverness last weekend. And we had suffered a setback, going 1-0 down to Kilmarnock, although the boys fought back in the right way. ‘All of the goals were my favourites. The first one was a great ball into the box by Kris Commons and I managed to head it down into the net. ‘The second one went in off the post and I was just waiting for the whistle to go for being offside for the third. Thankfully, it didn’t come and I fired it back across the goalkeeper. ‘It’s only my third hat-trick in senior football, so it’s decent. My second one came for Celtic against Inverness last year.’ Cute move, dropping that into conversation. Take note, gaffer? Not only am I bang in form, not only do I have a great record at Hampden, but I’ve shown I can do the business against Inverness. Celtic start as favourites on Sunday and, with Hibs also edging the odds in their semi against Falkirk, Griffiths could spend May 30 torn between professional pride and genuine love for his hometown team. Asked outright if he would like to face Hibernian, balancing up the desire to become a Treble winner against the need to condemn his boyhood heroes to at least one more year of Scottish Cup taunts, Griffiths admitted: ‘Honest answer, no! ‘If they get there, it will be great for the club, but I’m just concentrating on doing my job for Celtic. We are eight points clear in the league and in a good position and, obviously, we want to go for the Treble. ‘There is still a long way to go and we have difficult games coming up. At the moment, Inverness are standing in our way of having a potentially great season.’
Leigh Griffiths revealed that Ronny Deila and John Collins warned him . The Celtic striker took a while to settle in at his new club after his move . Griffiths has been in red-hot form and scored three against Kilmarnock .