Despite winning the tournament last year, Wales arrive at this season’s staging as only fourth favourites behind France, England and Ireland.
They go into the Six Nations on the back of a thrilling autumn win against Australia, although injuries have hit them hard.
British and Irish Lions like Alun Wyn Jones, Ken Owens, Leigh Halfpenny, Justin Tipuric and Josh Navidi are expected to miss the whole competition, while George North and Taulupe Faletau are only considered possibilities – at best – for the latter part of it.
Wales face a testing opener against Ireland in Dublin on Saturday week, before hosting Scotland and then tackling England at Twickenham.
“It’s a really tough start,” Northampton fly-half Biggar said, during the Six Nations virtual media launch.
“Obviously, with the form Ireland showed in the autumn – how impressive they are – and we know how tough going to Dublin is. We haven’t had a huge amount of success there over the last few years.
“This tournament, in particular, hinges on momentum, really.
“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 really important to get a good start.
“If you can pick up an away win on 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.
“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.
“We were written off last year. We are coming into the tournament as defending champions, so there is certainly a bit of a swagger in the group.”
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.
Biggar added: “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.”
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