Wales face a tricky Murrayfield opener against Scotland on Sunday, having being installed as the bookmakers’ favourites to land a second successive RBS 6 Nations crown.

Head coach Warren Gatland names his team tomorrow, with fit-again Ospreys stars Gavin Henson and Mike Phillips expected to make international comebacks after being out of the Test arena since last season’s Grand Slam-clinching victory over France.

Cardiff Blues wing Lee Halfpenny, meanwhile, looks poised for a Six Nations debut - having impressed during the autumn series, as Scarlets speedster Mark Jones continues his recovery from appendix surgery.

Defence specialist Edwards has left no one in any doubt that Wales mean business.

“I can only talk about what I have seen in the past eight days, and that has been absolutely exceptional,” he said.

“We did a lot of hard work last week with some pretty brutal training sessions. Some of them were as tough, if not tougher, than a game.

“You need a constant hunger to improve and be constantly challenging yourself and those around you.

“You need to be in an environment that, at times, can be a little uncomfortable - where you don’t settle for second-best. We have those sort of characters in the Wales squad.

“But it’s also that we have a pretty healthy squad. If you had told me that, after the autumn internationals, this would be the squad we had for Scotland, we would have been very happy.

“There is a lot of competition for the nines, 10s, the midfield and all over the pitch really. No one can be too comfortable because, if they get too comfortable, someone else will be in their spot.”

Wales are also rated the most likely team to win a Grand Slam this season, even though three of their matches - against Scotland, France and Italy - are away from home.

Successive championship clean sweeps were last achieved by France in 1997 and 1998, while Wales must go way back to 1908 and 1909 for their solitary double.

Any trophies and plaudits are some way off, though - and that is exactly how Edwards likes it.

He added: “You just have to keep your hunger to improve.

“If you keep improving on the core basics of rugby, the titles and trophies will follow on from it.

“If you start thinking about the end outcome, trying to go for a second Grand Slam, you forget about the process of actually getting there.

“That process is working hard in training, providing an honest analysis of games and doing the job on the field.

“Our focus is very much on Scotland and the next training session. I am a big believer in the here and now, and making sure we nail each individual training session.

“Warren has stated many, many times that we want to be regarded as one of the best teams in the world - and to do that we know we need to improve on where we are now.

“Results against the southern hemisphere in the autumn proved the northern hemisphere has a bit of catching up to do, even if I think we performed admirably in all of the games.

“But admirably isn’t good enough. There is no room for complacency with these players - not after the way we trained last week and with the standards Warren sets for himself, the coaches and the players.”

Wales’ magnificent defence underpinned the title success last term, conceding just two tries in the championship as only England back Toby Flood and Italy prop Martin Castrogiovanni crossed their line.

With tough taskmaster Edwards again formulating Wales’ defensive organisation, the gauntlet will be thrown down once more to opposition attacks.

“There is no doubt, defensively, it probably went beyond our wildest dreams last year - only conceding two tries,” he said.

“Whether we can be as accurate as that, I don’t know.

“We are always hopeful, But in the end the game is judged on whether you win or lose.

“Obviously, as defence coach, I’m happiest when they (opponents) don’t score any tries - but so long as we win, that’s the main thing.”