Celtic have written to the Scottish Football Association in order to gain an 'understanding' of the refereeing decisions during their Scottish Cup semi-final defeat by Inverness on Sunday. The Hoops were left outraged by referee Steven McLean's failure to award a penalty or red card for a clear handball in the box by Josh Meekings to deny Leigh Griffith's goal-bound shot during the first-half. Caley Thistle went on to win the game 3-2 after extra-time and denied Rory Delia's men the chance to secure a domestic Treble this season. Celtic striker Leigh Griffiths has a goal-bound shot blocked by the outstretched arm of Josh Meekings . Celtic's Adam Matthews (right) slides in with a strong challenge on Nick Ross in the Scottish Cup semi-final . 'Given the level of reaction from our supporters and across football, we are duty bound to seek an understanding of what actually happened,' Celtic said in a statement. They added, 'We have not been given any other specific explanation so far and this is simply to understand the circumstances of what went on and why such an obvious error was made.' However, the Parkhead outfit made a point of congratulating their opponents, who have reached the first-ever Scottish Cup final in their history, describing Caley as a 'fantastic club' and saying 'reaching the final is a great achievement.' Celtic had taken the lead in the semi-final through defender Virgil van Dijk's curling free-kick on 18 minutes, but were unable to double that lead thanks to the Meekings controversy. It allowed Inverness a route back into the game and Celtic had goalkeeper Craig Gordon sent off after the restart for scything down Marley Watkins in the area. Greg Tansey duly converted the resulting penalty. Edward Ofere then put Caley Thistle ahead, only for John Guidetti to draw level for the Bhoys. With the game seemingly heading for penalties, David Raven scored the winner on 117 minutes, breaking thousands of Celtic hearts. Celtic captain Scott Brown (left) protests to referee Steven McLean but the handball goes unpunished . Griffiths shows off his acrobatic skills during Celtic's eventual surprise defeat by Inverness . Celtic pair Aleksandar Tonev (left) and John Guidetti look dejected as their hopes of a domestic treble end .
Celtic were defeated 3-2 after extra-time in the Scottish Cup semi-final . Leigh Griffiths had a goal-bound shot blocked by a clear handball . However, no action was taken against offender Josh Meekings . The Hoops have written the SFA for an 'understanding' of the decision .