The defender is quite aware that the story of his career could be very different had he not sought a move north in 2012, signing that summer for Inverness Caledonian Thistle.
That move has since taken him to a League Cup final and will veer once more towards Glasgow and a league match with Celtic. On the trip down for today's meeting with the SPFL Premiership champions the necessity will be to try and make the journey from the Highlands pass quickly, or catch up on a bit of sleep. Warren would perhaps be able to nod off by counting up all of the various jobs which he might be doing had football not worked out.
The game has brought the Englishman close to glory, but he acknowledges too that it has also taken him away from a life spent working as a day labourer and training to be a school teacher. His career path has led him to appreciate what he now has - spells in the English non-league football with Mangotsfield United and Team Bath, followed by a move to Newport County and then Inverness.
"I enjoy every Saturday game, whether it's playing at Celtic Park or anywhere else," said Warren. "I'm thankful for what I'm achieving at the moment. To come from working on a building site and teaching, it's really a dream come true. If anything, playing at Celtic Park in front of 60,000 fans is much easier than standing in front of 30 little buggers in a classroom.
"When I'm finished, I'll look back on my career and see that when I was a youngster I wanted to play professional football and I've achieved it. Playing at places like Celtic Park is always what I wanted to do."
A dalliance with teaching has at least allowed Warren to assess his side's capacity to break into the European places before the end of the season. Inverness are currently fifth in the table and eight points adrift of third, with 12 points still to play for.
"Top three is still the aim because it's mathematically possible so we'll keep going until it isn't," he said. "The boys were disappointed last year that we finished fourth so we want to go one better. We can beat last year's points total, have got to a cup final and got into the top six for a second time.
"The challenge for the club now is to build on it and become a regular top-six side. We have to kick on from this, we want to continue and carry on from the success we've had."