After round three of the RBS Six Nations, England remain the only team with a 100% record after securing a 21-10 win over Ireland.
However, Wales still remain contenders after a 19-10 win over a below-par France side.
The game of the weekend saw Scotland enjoy a victory over Italy in Rome as Vern Cotter's men stormed to a 36-20 win to end their nine-match losing run in the Six Nations.
The weekend starts in Dublin on Saturday afternoon as Ireland play host to Italy at the Aviva Stadium, in a must win for both sides as neither have won a game as of yet. England welcome Wales to Twickenham with a potential triple crown on the line, whilst Sunday sees France travel to BT Murrayfield to face Scotland.
Irish hoping to get off the mark
Ireland and Italy go head to head this weekend with both trying to salvage some pride before the tournament concludes. Ireland have had a title defence from hell, having not won in this year's tournament after an opening draw with Wales was followed up by two straight defeats to France and England.
However, the Italians are in danger of finishing without a win themselves as defeats against France, England and Scotland have resulted in the side sitting bottom of the table. Out of the 25 occasions that the pair have met, Ireland have won 21 times including a 16-9 victory in last year's Rugby World Cup.
Ireland have made two changes, as Jared Payne has recovered from injury to start at centre whilst Simon Zebo replaces injured full-back Rob Kearney. Stuart McCloskey, who made an impressive debut against England a fortnight ago, drops out of the squad altogether, whilst skipper Rory Best is set to make his 50th championship appearance.
Fly-half Edoardo Padovani makes his first start as one of four changes for Italy, along with Guglielmo Palazzani, David Giazzon and George Biagi. Palazzani will be making his first start in the Six Nations as he replaces injured Edoardo Gori. The Zebre fly-half replaces the injured Kelly Haimona while the other changes see hooker Giazzon and lock Biagi taking over from injured pair Leonardo Ghiraldini and Josh Furno.
Championship decider at Twickenham
England and Wales meet at Twickenham this weekend with plenty on the line, as the home side could secure a triple crown trophy having previously over come Scotland and Ireland already. In last season's fixture, England came from behind to win 21-16 in Cardiff but it was the Welsh who enjoyed a World Cup win last year to effectively end England's hope of progressing further.
A win for Wales this weekend would give them a huge opportunity to secure the championship, as both England and France play each other on the final weekend whilst the Welsh will come up against Italy.
After another win over the Irish, Eddie Jones has named an unchanged side to face Wales on Saturday, but the big news in terms of replacements is that Manu Tuilagi returns after a 21 month absence. Luke Cowan-Dickie, Kieran Brookes and Joe Launchbury are all new to the side and will start from the bench ahead of the game.
Gareth Davies will remain at scrum-half as Webb starts from the bench whilst lock Luke Chateris also takes a place among the replacements, but Paul James comes in to cover injured Gethin Jenkins who suffered a calf strain against France. Front-row trio Rob Evans, Scott Baldwin and Samson Lee pack down for a fourth consecutive RBS 6 Nations match together whilst it is an unchanged back row of Dan Lydiate, Sam Warburton and Taulupe Faletau.
Scots hoping to upset the French
Since the creation of the Six Nations, Scotland have only ever enjoyed one victory over their weekend opposition. After securing a win over Italy last time out, the Scots will be looking continue their impressive performance.
Despite a below average performance against Wales, France still remain in the hunt for a six nations championship and a win in Edinburgh this weekend would set the French up for a huge encounter next weekend with England.
Scotland coach Vern Cotter makes two changes to the side that won in Rome a fortnight ago as Glasgow pair Alex Dunbar and Josh Strauss come into the side, with Ryan Wilson dropping to the bench and Mark Bennett not making the squad. South Africa-born Strauss will make his third start for Scotland, with No 8 David Denton sidelined with a groin injury.
France manager Guy Noves has made a number of changes to the side including Jules Plisson being replaced by Francois Trinh-Duc. Maxime Machenaud remains in the squad from the defeat in Cardiff, Scott Spedding is recalled at full-back, and Wesley Fofana returns from a rib injury. Gael Fickou also returns to the squad to partner Mermoz. Yoann Maestri is recalled in place of Paul Jedrasiak and Yacouba Camara comes into the side at No 8 with Damien Chouly moving to the openside.