This shocking Graeme Souness decision cost Newcastle United

One of his less-scrutinised decisions was that to sell Aaron Hughes to Aston Villa in the summer of 2005 for around £1million.

It wasn’t a high-profile mistake, but it was a mistake nonetheless.

The reason I’m writing this is that Hughes – who, memorably, made his Newcastle debut against Barcelona at the Nou Camp in 1997 as a teenager – has retired from football.

Hughes told his Northern Ireland team-mates after last night’s win over Belarus.

Captain Steven Davis said: "Aaron spoke to us after the game, and he was a little bit emotional, which is understandable. He’s been a huge player for us over many years, and he’ll be remembered as a proper legend.

"Aaron still looks as if he could play on, but if he’s made a decision to retire, we've got to respect that and wish him well."

Hughes had made 278 appearances in a first-team career spanning eight seasons by the time he left at St James’s Park.

The Cookstown-born player – who had come up through the ranks at United’s Academy – had been a classy defender for the club.

Yet the way the club handled his exit was classless. Hughes was informed a bid had accepted by a club official in a brief telephone call. That was that. He was off to Villa Park. Souness – who had signed Boumsong for £8.5million five months earlier – didn’t make the call.

At the time I spoke to Hughes, who spoke warmly and affectionately about the club and the fans who had supported him through his career on Tyneside. However, it was clear he was taken aback, and a little upset, by the way the club had handled his departure.

Hughes deserved better. The versatile player went on to have a very good career for club and country, and was still playing Premier League football with Fulham up until 2014.

Boumsong, meanwhile, turned out to be a disastrous buy, and was gone the following year.

Sometimes, you don’t know what you’ve got until it’s gone, and Hughes was missed for many years after his hurried sale.