Celtic defender Virgil van Dijk insists their season will still be a success if they clinch the Scottish Premiership title . Manager Ronny Deila had targeted the treble in his first season but that dream ended in controversial fashion with a 3-2 William Hill Scottish Cup semi-final defeat by Inverness on Sunday . Deila started with a disastrous Champions League qualifying campaign when Celtic were knocked out by both Legia Warsaw and Maribor , but went on to impress in the Europa League and domestic scene with the League Cup already in the trophy cabinet following an absence of six years . Celtic defender Virgil van Dijk celebrates with his team-mates after scoring in the Scottish Cup semi-final . Van Dijk , who scored Celtic 's opener against Inverness , wants his side to bounce back and win the SPL title . And Van Dijk is now looking to wrap up the title in style to get over his Hampden disappointment . Celtic can reopen an eight-point lead over Aberdeen by winning at Dundee on Wednesday night ahead of the post-split fixtures . 'If we win the league we still improve from last year , ' Van Dijk said . 'We want to win it as soon as possible and that starts on Wednesday . 'The disappointment is very high , everybody is down but we are professionals and we need to focus on Dundee . 'We need to move on . Wednesday night at Dundee is a big game , so we need to be ready for that . ' Celtic striker Leigh Griffiths accused the match officials of robbing them a cup final appearance after they failed to spot his goal-bound header being stopped by the hand of Inverness defender Josh Meekings when the Hoops were leading 1-0 . But Van Dijk refused to dwell on the blunder by referee Steven McLean and additional assistant Alan Muir , who was five yards away . When asked about the penalty claim , the Dutch defender said : 'It did n't happen so we ca n't talk about it . Hoops striker Leigh Griffiths sees his headed effort strike the outstretched arm of Inverness ' Josh Meekings . Celtic captain Scott Brown appeals to referee Steven McLean , but no penalty is awarded for the handball . Celtic 's Adam Matthews ( right ) slides in with a strong challenge on Nick Ross during the match on Sunday . 'We look at our own performance and we lost and we are not on for the treble anymore . 'It should have been a key moment but it did n't happen so there is nothing to talk about . We lost and we are very disappointed . ' Van Dijk opened the scoring at Hampden when he curled a free-kick in off the post but he and Jason Denayer were given a tough afternoon by the pacy Marley Watkins and powerful Edward Ofere , who scored Caley Thistle 's second goal . 'We gave everything , ' he said . 'With 10 men we kept on fighting . We had quality to score a goal but unfortunately it was n't enough . ' Griffiths tries his luck with an acrobatic overhead kick on goal during the Scottish Cup semi-final on Sunday .
Celtic missed out on the chance to secure a domestic treble after coming out of the Scottish Cup semi - final 3 - 2 to Inverness on Sunday . The saints were controversially denied a penalty after a blatant handball by Inverness ' Josh Meekings in the area . Still , with the League cup already won in March , Celtic have the chance to win two trophies if they successfully clinch the SPL title . fi ##lip van Dijk wants to wrap up the league as soon as possible .