THE text flashed up on Andy Halliday's phone as the Bradford City team bus pulled into Stamford Bridge.

"At any time," read the message from an old pal, "your whole life could change." The 23-year-old Glaswegian noted it before moving, somewhat wearily, on to the next item in his inbox. Surely that old guff about the magic of the FA Cup didn't still hold in 2015?

What happened next might not have been down to text messages or fate but it did restore many people's faith in modern football. Goals from Gary Cahill and Ramires had the Kings Road millionaires two-up and strolling before the League One side compiled the unlikeliest of comebacks.

We were back on level terms, courtesy of goals from Jon Stead and former St Johnstone player Filipe Morais before the moment on 81 minutes which changed this former Livingston midfielder's life forever. Immortalised on the T-shirts and hoodies of many of the Bradford fans who will attend Valley Parade today as they attempt to prolong the fairytale against Barclays Premier League Sunderland is the image of Halliday guiding a Stead cut back sweetly beyond Petr Cech, and sliding on his knees in celebration towards the 6,000 travelling support. Halliday had been taken off with cramp by the time Mark Yeates got the clinching fourth, and was far too busy collecting his man of the match champagne and conducting his round of post-match interviews to witness Jose Mourinho coming into the visitors dressing room afterwards and praising them for their achievement.

"It is a couple of weeks on now but it still feels surreal," Halliday told the Sunday Herald last night. "A daft wee boy from Glasgow has obviously gone and scored the winner at Stamford Bridge in a match which has been called one of the biggest FA Cup upset ever.

"It wasn't just the result, it was the performance," he added. "In the second half we absolutely battered one of the best teams in Europe. It was domination and we could have scored more than we did. It spoke volumes that Chelsea had to bring on [Cesc] Fabregas and [Eden] Hazard, the best players in the world. They obviously thought they were going to kick on.

"I was lucky enough to get the man of the match award but I missed everything. Because of the magnitude of the game I had far more interviews to do, I had to do Talksport and everything. I didn't manage to get anybody's jersey either, but the most important one was mine. Once I get it framed, that will take pride of place on my wall."

It has taken a fair while for Halliday to become an overnight success. As a teenager, he was cheerfully dreaming of a career at his boyhood heroes Rangers, playing a year above his age group at Murray Park. His body protested, however, a lay-off due to growing pains leading to his release at the age of 15. "It was a devastating period for me," he said. "I actually chucked football for six months after that, I was just having a kick-around with my mates."

Scott Allison, a respected youth coach now at the Thistle Weir academy, persuaded him to come to West Lothian, and it wasn't too long before he was making his first team debut against St Johnstone at the age of 16. Also in Mark Proctor's team that day in April 2008 were Robert Snodgrass, Graham Dorrans, Leigh Griffiths and Murray Davidson.

After a haul of 16 goals in his first full season at Almondvale, it was on to Middlesbrough and the brave new era of Gordon Strachan, alongside such luminaries as Kris Boyd, Scott McDonald, Stephen McManus and Kevin Thomson. It is a period that not too many look back on fondly, but Halliday's main regret is the groin problem which curtailed his time there.

"What a lot of people maybe don't remember is that I played pretty much every game I was fit under Gordon Strachan," said Halliday. "My injury came about just before he parted company with the club. It took me a long time to get back in after that, because Tony Mowbray came in and he just saw me as a young boy who had been out for a period of time.

"I am still young enough but I have never even thought about the Scotland set up, because there are so many good Scottish players already there," he added. "In my opinion it is probably the strongest Scotland squad there has been for a long period of time. It hasn't crept into my mind but I had a good relationship with Gordon Strachan at Middlesbrough, and one day I would love to work under him again, whether that meant I was fortunate enough to get a Scotland call-up or not."

A loan spell in Barry Ferguson's short-lived Scottish enclave at Blackpool last season led to a similar arrangement at Bradford, while the permanent deal which allowed him to play at Stamford Bridge was tied up fully three minutes before the January window. Steven Fletcher, one of his football pals, awaits at Valley Parade this afternoon, in a match mystifyingly ignored by the broadcasters.

"I know Fletch and he is somebody you can look up to," said Halliday. "I always look out for his results and it is good to see him doing well. It will be good to see a friendly face on Sunday, but hopefully I can get one over on him."