FOOTBALL has yet to fully embrace the sort of in-depth statistical analysis pervasive in most American sports.

And more's the pity. But in assessing just how pivotal Celtic's defence has been in their stroll to a third consecutive Scottish title then the raw numbers are revealing.

Consistency of selection has been key to their success. Following last night's victory over Partick Thistle, Celtic have now played 31 league matches this season. Goalkeeper Fraser Forster has started every one of them. Efe Ambrose has started in all but one, last weekend's victory over St Mirren when he came on as a substitute. Virgil van Dijk, enjoying an outstanding maiden campaign, has missed only two matches, one not long after his arrival and another recently due to suspension. Emilio Izaguirre has also played in all but two of the games.

Only at right-back has there been something of a job-share arrangement, largely as a result of injuries. Adam Matthews has started in 18 of the 31 league games - some at left-back - Mikael Lustig just seven, while the promising Darnell Fisher has started in 10.

Such synergy has delivered tangible results. Celtic have conceded just 15 league goals this season. By the same juncture last season they had let in 29, the year before 20. Indeed, before Christie Elliott's late consolation last night you had to go back to Ivan Sproule's goal for Ross County in a 4-1 defeat in early November to find the last team apart from Aberdeen to score a league goal past Celtic.

Landmarks have been set. Forster first claimed the Celtic clean sheet record, surpassing Charlie Shaw's achievements from 1922, then overtook Bobby Clark's Scottish league record which had stood for 43 years. The Englishman deserves the accolade for the vital saves he made along that journey although he was quick to acknowledge the importance of his defenders in keeping opposition attackers at bay. It says something about Celtic's defensive strengths, as well as their mental fortitude, that once the run was ended last month by Aberdeen's two goals, they immediately set off on another one.

The tale of the Englishman, Honduran, Nigerian and Dutchman sounds like the start of a convoluted, non-PC joke. Instead it is how a cosmpolitan Celtic backline has provided the defensive platform a championship has been built on.

"Consistency of selection is a massive thing," said Tom Boyd, the former Celtic defender. "You create an understanding with each other, a telepathy almost. People talk of strikers linking well together and it's the same for defenders as well.

"You've got to get on with each other as well and that seems to be the case. You can't better what Celtic are doing defensively at this moment in time in terms of clean sheets. You have to say they're all playing at the top of their game, judging by their performances."

Van Dijk's shaky first start for Celtic - the 2-0 Champions League defeat by Shakhter Karagandy - now seems like a lifetime ago. The Dutchman has been a revelation, a central defender who can mix the unglamorous business of clearing his lines with meandering surges up the field. His agent has already started making predictable noises about the lure of England and his departure would leave a void that manager Neil Lennon would struggle to fill.

"Virgil has slotted in really quickly since his arrival," added Boyd. "He and Efe seem very comfortable with each other and know the other's style of play. The key thing is how comfortable they all are on the ball, and able to break up the park as well as we saw with the goal Virgil scored at St Johnstone.

"Virgil is up there in terms of Player of the Year alongside Kris Commons and Fraser Forster for me. He's got another three years of his contract left so I hope he at least stays for a few more years before he moves on. If someone was to come in for him, and there are a few teams in the English Premier League who will be looking for centre backs, then there could be a bidding war.

"Neil Lennon has said he's perfectly happy with the situation but if £12m comes in, similar to Victor Wanyama, then that could be the start of it. I think you would be looking in excess of that for Virgil."

Forster is another likely to attract admiring glances from a number of English clubs this summer. His rating, and subsequent transfer value, would rise further should he make Roy Hodgson's final England squad for the World Cup finals in Brazil. Boyd believes the goalkeeper merits a seat on the plane.

"Fraser should be going to the World Cup," he added. "The save he made against Sam Stanton in the Hibs game was world-class and he made a lot of important stops like that during the clean sheet record. Joe Hart is England's first choice but among the others contending like Ben Foster or John Ruddy I don't see that same level of consistency.

"For me it should be a no-brainer but we'll see what Roy Hodgson decides. But for selfish reasons I hope he gets a rest this summer."

n Boyd was speaking as Street Soccer Scotland announced a £1m sponsorship agreement with Powerleague, the UK market leader in 5-a-side football