The Calcutta Cup clash is a very important match for Scotland because it really sets the tone for the rest of the tournament.
If they go out at Twickenham and they play well, then it could be really close and Scotland could come away from it with an awful lot of credit.
England will be desperate to regain some confidence after the battering they have taken during the last nine to 12 months.
Wales will fancy their chances against the Irish at the Millennium Stadium in front of a massive crowd. If they get off to a great start, that will really dent Ireland's confidence.
Ireland are going into this RBS Six Nations Championships are favourites and momentum is so important in this tournament. They had a very good series of autumn internationals and they showed they have one or two areas where they do have real strength in depth.
International fixtures come thick and fast, week after week and it's a chance to create momentum. It's much easier to sustain momentum when you're winning.
Italy in Rome could be quite a difficult proposition for France, who were clinically dismantled in their first Test against New Zealand.
Italy have a very capable set of forwards and I wouldn't write them off against France this weekend. France have said they're already focusing on the World Cup, not the Six Nations.
If that's the case, then they've discounted the tournament already. You do just wonder what mental attitude they're going to be taking into the competition.
Wales flanker Sam Warburton admits he will be proud to lead his country out for a record 34th time this weekend and hopes to cap the day off with a memorable RBS 6 Nations victory against in-form Ireland.