Mr Stewart, a popular singer, m'lud, wept openly as his team, Celtic, defeated Barcelona on Wednesday night. It is presumed the tears were of happiness, though Rod's crying would only have made sense to most of us if it had come after he had been told Paddy Power had offered 10-1 on a Celtic victory and he hadn't had a punt.
His reaction may have betrayed Rod's upbringing in England. Scots do not do crying with happiness. Frankly, we don't really do happiness and certainly not at the fitba'.
As my old mate Tam used to say: "If fitba' was meant to make you happy it would be licensed with a free bar."
Crying in football for the true Scot tends to involve, pain, loss and, of course, anger. Thankfully, these stages of the Scottish sporting psychology are encountered early in life and thus the process is inculcated almost in infancy.
The message is bluntly consistent: football is meant to hurt. This is why weans once played on ash parks with balls that had about as much give in them as a Yorkshireman at a charity auction. It is also why football boots were constructed to double up for use in the pits and had soles that allowed so many nails through that one had to acquire all the resilience of an Indian fakir.
All this has changed, of course. Weans play on grass with dinky wee goals while wearing hi-tech slippers. And sometimes they seem happy. This is not the Scottish way and may just have a correlation with the lack of great players coming through.
Once Scots did not play football to be content, but because there was sod all else to do.
The experience of the fan, of course, is the pursuit of a manageable depression, a nagging misery rather than any search for elation. It is why stadiums were once constructed so that the supporter had no dignity, little comfort and a surfeit of close encounters of the insanitary kind.
The punter is so traumatised by this past that, when the stadium offers him a seat, he tends to stand anyway. Having a wee seat, after all, would be coming dangerously close to being happy.
There is a place for tears but it is normally reserved for either situations of loss or anger, sometimes both. I have played with team-mates who cried softly during games until victory was assured. They would wipe their eyes, stating that the sweat was running in from their nappers. We would look away swiftly, entering the repressed emotion mode we learned at our father's knee and other low joints.
A bad loss can also bring a dose of greetin', but rarely. First, we are conditioned to getting beat. Second, it never does to show anybody how much a wee game of fitba' hurts, particularly to your mates who support the other side.
Tears may be at a premium for the Caledonian punter but there was another moving instance of them far from Rod and the Celtic Park main stand. Fabrice Muamba, the former Bolton Wanderers player, walked out on to White Hart Lane on Thursday, eight months after collapsing on the park. His heart had stopped beating for more than an hour but, incredibly, the young man survived.
There was an eeriness about his visit as he pointed to the spot where he fell, the precise piece of grass that might have felt his last breath had not expert medical attention been given to him almost immediately.
The crowd roared and Fabrice saluted them for their support, while wiping tears from his eyes.
Football is mired in petty politics, occasionally scarred by racism, blighted by greed and pock-marked by scandal. It is, in short, like much of life.
But it has the capacity to bring tears of joy to Rod and to Fabrice. It has also has the ability to show the fan at his or her best whether that be defiant in defeat, euphoric in victory or just heartily and lustily gratified that another human being has survived a perilous event.
It could bring a tear to a Scottish eye, but only perhaps if one was wearing a boot with a nail in it.