The Bhoys were favourites to win the Scottish Cup semi-final tie against their Scottish Premiership rivals at Hampden Park in Glasgow.
However, 10-man Celtic went down 3-2 to Inverness after extra time, with David Raven scoring the winning goal in the 117th minute of the encounter.
Former Scotland international Commons, who featured for 90 minutes, is disappointed with the defeat and has highlighted the main reasons why John Hughes’s side managed to get the better of them.
“I thought we did enough – a few things didn’t go our way on the park,” the 31-year-old former Nottingham Forest star told Celtic’s official website.
“But credit to Inverness. They worked hard, put us under pressure and to score three goals against us means they always had a chance. We gave everything. There was nothing more we could have done.”
It is really great of Commons not to look for excuses and give due credit to Inverness, especially as Sunday’s game was a controversial one.
Leigh Griffiths's goal-bound shot was seemingly blocked by the hand of Inverness defender Josh Meekings. The penalty was not given, and that could have changed the final outcome of the contest.
However, such decisions are quite common in football, and the main point is that on the day Inverness were the better team.
Celtic conceded as many as three goals over the 120 minutes, and that needs to be looked at in the coming days.