It's not been easy being a Colchester United supporter over the last decade or so.

But their demoralising FA Cup exit at home to non-league opposition undoubtedly resulted in one of their biggest single disappointments in recent times.

It might not be particularly comforting to disgruntled U’s fans who are probably still hurting today, after seeing dumped out of the cup at the first-round stage against National League South strugglers Oxford City.

But Colchester being humbled on their home turf – and their plucky part-time visitors’ wonderfully spirited performance – was a perfect example of how nothing can be taken for granted in this world-famous competition.

It was not as if John McGreal had not paid maximum respect to his side’s opponents, in the build-up to the tie.

The U’s head coach had City watched on several occasions, scrutinised video footage of their performances and left no stone unturned in his preparation for the match.

Indeed, the fact that McGreal named an unchanged starting line-up and resisted temptation to rest players – unlike some of his EFL counterparts - was a key indicator of how seriously he treated the visitors’ threat.

So what went wrong?

Quite simply, Colchester’s performance fell well below their recent high standards and that, coupled with City’s excellent organisation and spirit, culminated in a giant-killing.

They were off colour in all areas of the pitch particularly in attack, where they lacked composure in front of goal and were unable to reproduce the kind of prolific form seen under McGreal, at the Weston Homes Community Stadium.

The U’s boss is understandably keen to draw a line under the shock defeat and move on.

That is essential, with a derby at Southend United in the Checkatrade Trophy tomorrow night followed by an important League Two game at Barnet to follow, this weekend.

It is crucial that the U’s bounce back quickly from this major setback in their season.

How realistic that is after such a damaging and humiliating defeat, only time will tell.