Six Nations 2013: We know how to stop England's Manu Tuilagi spoiling Wales' clean sheet, says Jonathan Davies

The sides meet in a Six Nations decider this Saturday

Wales have now played 276 minutes of Six Nations rugby – very nearly three and a half matches – without conceding a try. So when Jonathan Davies, their outside centre, describes this climactic week as "normal", it is enough to chill red-rose bones to the marrow. If complete defensive security is the new normal, a first England Grand Slam in a decade is a good deal further away than the men from Twickenham might have hoped.

Davies, born in the English Midlands but very much a man of Llanelli, did not have the happiest of starts to the tournament, but his form in recent matches has reinstated him as a serious contender for the forthcoming Lions tour of Australia – a trip for which his playing partner, Jamie Roberts, has already been inked in. Together, the two midfielders pose a significant threat to English ambitions.

"We've been involved in these huge matches before," said the Scarlets player, who will square up to the freakishly powerful Manu Tuilagi in Cardiff. "With the Grand Slam last year and the World Cup semi-final in 2011, we're drawing on some rich experience. When you're used to the big-game environment and you know what to expect, you can just get your head down and play."

The Davies-Roberts relationship is on the point of being venerated as the steadiest in Welsh rugby history: this game, their 14th together, will see them beat the record set by Ray Gravell and Steve Fenwick in the late 1970s and early 1980s. "People said we were too similar and couldn't play together," Davies commented, "but if we set a new mark, it will be testament to our hard work. It's taken a while, but we've come a long way."

Might Tuilagi spoil the celebrations with his trademark stampedes through the heavy traffic? Davies did not sound like a man petrified by the prospect of stopping England's most powerful runner in his tracks. "Tuilagi and Brad Barritt are a strong pairing but Sam Warburton [the Wales flanker and recent captain] showed at Twickenham last year how you tackle Tuilagi. He took him low, around the ankles, and it was an effective approach.

"Basically, we have to trust our defensive patterns and follow what we've done in the last few games, which has been really impressive. To go three matches without conceding is a big plus for us and we'll be looking to keep it up."

Rob Howley, the former scrum-half who has shouldered the head coach's burden in this competition while Warren Gatland concentrates on Lions business, will name his side today. There are precious few decisions to be made, although the injury suffered by the blind-side flanker Ryan Jones at Murrayfield last weekend, together with the strong scrummaging performance of the Bath prop Paul James, has given him something to ponder in the wee small hours.

Justin Tipuric, the Ospreys breakaway, is expected to feature alongside Warburton, his fellow groundhog, in a reshaped loose-forward combination. As for the front-row issue, Howley must decide whether to recall his most experienced prop Gethin Jenkins after a successful recovery from calf trouble.