Captain Dan Biggar says Wales will have a "swagger" in the Six Nations despite the disrupted build-up to their title defence.

Wales also enter the tournament to the backdrop of domestic gloom, with the four Welsh regions struggling.

"We were written off last year," said Northampton fly-half Biggar.

"We are coming into the tournament as defending champions, so there is certainly a bit of a swagger in the group."

As well as Jones, Wales' long list of injured absentees means they are missing his fellow British and Irish Lions Ken Owens, Justin Tipuric, Taulupe Faletau, Josh Navidi, Dan Lydiate, George North and Leigh Halfpenny, who boast more than 700 Test caps between them.

"It is a tough challenge this year," said Biggar.

"From our point of view, there are lots of key experienced players missing, but that also gives an opportunity to a lot of young lads who have come into the squad to step up and really stake a claim."

Wales face a daunting first fixture away against Ireland, who defeated New Zealand in the autumn.

"It's a tough start," said Biggar. "With the form Ireland showed in the autumn, how impressive they are are, we know how tough going to Dublin is.

"We haven't had a huge amount of success over the last few years there.

"This tournament, in particular, hinges on momentum. If you get off to a good start, then everything seems to flow, camps become a lot happier and training becomes a lot easier. For us, it is important to get a good start.

"If you can pick up an away win the first weekend, then it sets you up really nicely. We have then got Scotland at home, which we know is going to be hugely difficult as well.

"The opening couple of weekends are pivotal to how the tournament will go for you, and we are hoping we can get off to a good start and use the 10 days or so we've got now to give ourselves the best chance in Dublin a week on Saturday."

Biggar will be up against Ireland fly-half and captain Jonathan Sexton, a team-mate of his on the Lions tour of New Zealand in 2017.

"The respect for Johnny has been from day one and the success he has had with Ireland and Leinster," said Biggar.

"I got on really well him in 2017 and just kept in touch with him ever since. We are similar character who demand a lot from ourselves and a desire to scrap for everything and to win."

Including Lions Tests, Biggar is due to play his 100th international against Scotland on 12 February, while his century of Wales caps could come in the tournament finale at home to Italy on 19 March.

"It's impossible for it not to be on my mind at the minute, which would be a hugely special achievement," said Biggar.

"My attitude is I want go on and get a fair few more than 100 and that means I've still got to make sure I'm playing well and keeping fit.

"I suppose it would be vindication because it has not been plain sailing throughout the 13 years I have been playing for Wales. It would be nice to do that personally and vindication to get there and prove I have done ok in this jersey over the years.

"Hopefully it can be a special campaign for myself, but more importantly, if I was to win my 100th cap in a Six Nations decider at the Principality Stadium, I probably couldn't script it better than that."

Jones, the most capped player in Test rugby union history, has undergone two shoulder operations since being injured during Wales' Autumn Nations Series opener against New Zealand in October.

He also had shoulder issues ahead of last summer's Lions tour to South Africa, but he defied expectation and recovered in time to captain the tourists in all three Tests.

Jones is expected to miss the tournament with Pivac admitting it was a "long shot" he could feature in this tournament.

Biggar says he has taken captaincy advice from Jones, adding: "I don't think any of us expected him to turn up in South Africa in the summer, and he managed to get on the plane.

"If there is anybody who has got a chance of being fit for some part of this tournament, then Al is probably the man. I wouldn't rule it out just yet."