BATHED in bright, late-summer sun one of football oldest rivalries returned after a four-year hiatus, accompanied by a dark and age-old problem: sectarianism.

There was just one arrest inside the ground as Celtic beat Rangers in the first league encounter of the season 5-1 – a 22-year-old man for an alleged alcohol-fuelled incident. And while a toilet and washing room area in the visiting supporters' end of Celtic Park was badly vandalised, it was when the Sunday Herald took to the streets that we found the sectarian tensions associated with the Old Firm were very much in evidence.

Sectarian and racist chanting, the waving of flags and banners associated with the Northern Ireland Troubles, as well as aggressive flashpoints at a heavily policed match were all on show in a way that implied the worst elements of the clash were back.

Yet again, it was the behaviour of a minority of fans before and after the match that showed the ugly and shameful side of the historic encounter. Tensions surrounding the two teams had largely been left to simmer on social media forums during the enforced absence of the fixture which brings out one of the fiercest, some might say ugliest, rivalries in European football. Rangers had been relegated to the bottom tier of the Scottish Professional Football League but, after the four-year banishment, were back.

And when Glasgow got its first taste of the infamous league derby yesterday, issues that have given rise to anti-sectarian legislation were arguably as prevalent as they were when the exile of Rangers from football's summit began.

The Sunday Herald witnessed a series of aggressive incidents, including a female Rangers fan in her twenties who assaulting a male Celtic supporter walking alone past a crowd of supporters of the Ibrox club after she had managed to get past the police.

Police officers patrolling London Road opposite Celtic's stadium stopped the woman, whose Rangers scarf fell to the ground during the incident, and warned her about her behaviour, but allowed her to walk on towards the match without arrest.

Another male Rangers fan was warned by a police officer he would be arrested after he was heard shouting abuse and swearing at passing Celtic fans.

There was also repeated chants in support of loyalist paramilitary groups the UVF and UDA by a hardcore group of Rangers supporters who stood facing the ground for more than an hour right up to kick off. Other chants aimed at Celtic fans from their Rangers rivals included one of "paedo" and "Jimmy Savile is one of your own" by groups carrying flags bearing the Red Hand of Ulster, as well as the Union flag.

However, there was loud pro-IRA chanting and singing from sections of Celtic supporters close to the Celtic Park stadium and in nearby pubs.

Police were also called to an incident at the Rosevale bar in Dumbarton Road last night where witnesses reported seeing "blood all over the steps" after what was believed to be a glassing attack. The pub was previously owned by former Rangers manager Walter Smith.

A man, believed to be in his 30s, was taken to hospital after apparently being injured in the attack. No arrests were made.

A Police Scotland commander said the majority of fans had behaved in a "safe and responsible manner" but the force confirmed that one matchday arrest had been made. A police spokeswoman added that the toilet vandalism is currently being dealt with internally by Celtic and no arrests have been made over it.

Dave Scott, campaign director of anti-sectarian charity Nil by Mouth, said there remained a minority of Old Firm supporters "living in the dark ages" who see the re-emergence of the Glasgow derby fixture as a "hook for wilful and hateful ignorance".

Despite Police Scotland talking about the "good spirits" from supporters on both sides of the Old Firm divide, a heavily policed fixture saw both sets of fans mostly kept well apart both before, during and after the midday kick-off. Rangers fans were marched towards the stadium close to a cordon lined with police vans and officers on horseback all along London Road, while the home side supporters were moved along the route from Gallowgate.

Scott added that the catalogue of incidents showed that there remained a hardcore intent on using the Old Firm tie as a forum to spread sectarian hatred and bigotry.

He said: "The situation is better than it was 20 years ago and the majority of fans were either happy or sad with the result and then enjoyed a pint afterwards. But sadly there remains a voyeurism around the Old Firm, with people spending time on social media antagonising others.

"There are people who use this match as a hook for wilful, hateful ignorance. It's a sizeable minority that are living in the dark ages and clubs have to deal with this issue."

Scott maintained that the problem of Old Firm sectarianism would remain unless strict liability was introduced, where clubs can be punished with points deductions for the conduct of fans regardless of whether the club itself is to blame.

Meanwhile, pubs close to the ground such as the Turnstiles bar, full of home fans watching the match live on TV, were shut in by staff at full-time with the supporters locked inside due to fears about clashes with the departing Rangers crowd.

Police also closed off two exits along London Road to prevent opposing fans coming into contact with each other for nearly 30 minutes after the final whistle, a technique known as kettling. Chief Superintendent Brian McInulty, commenting on Police Scotland's matchday operation, said: “I would like to thank all the supporters who came to enjoy the match today in a safe and responsible manner."

Meanwhile, the Scottish Government said the Offensive Behaviour at Football and Threatening Communications Act passed in the last parliament "sends out a clear message" and had helped to curb sectarian behaviour at matches. That message had clearly not been heard by many of the fans outside Celtic Park.