After a weekend off following the first two sets of fixtures, the Six Nations returns on Saturday with Ireland seeming in all-conquering form, England unbeaten and Wales still looking for their first win of the tournament.
England travel to Edinburgh to play Scotland on Saturday after Ireland host Wales, before Sunday's clash between France and Italy.
Here's all the team news and everything you need to know heading into the weekend.
Ireland vs. Wales, Saturday 2.15pm, Aviva Stadium, Dublin
Fly-half Sam Costelow returns from injury in the only Wales change from their last Six Nations outing.
Costelow missed the 16-14 loss to England in their previous game two weeks ago with a neural neck injury but is back in the side that coach Warren Gatland named on Tuesday.
Cardiff No. 8 Mackenzie Martin was named among the substitutes for the first time and is in line for his first cap if he comes on against the Irish.
The 20-year-old from Cardiff replaces Taine Basham in the 23-man squad and could become Wales' 1,200th international.
Wales are looking for their first success in this year's Six Nations but are up against a rampant Ireland, who have won both their opening fixtures.
"We've made steps in the last couple of games and now it's about building on that, learning from those experiences and taking that into this weekend," Gatland said in a statement.
Meanwhile, Ciaran Frawley will get a first start for Ireland after being selected at fullback as Farrell named a strong team for the Dublin clash.
Peter O'Mahony returns to captain the side as Ireland on Thursday also recalled Bundee Aki, Tadhg Beirne, Tadhg Furlong, Jamison Gibson-Park and Josh van der Flier to the starting lineup.
They had rested several key players for their last game against Italy, which they won 36-0 in Dublin to make it two wins from two games in this year's championship.
Ireland: Ciaran Frawley, Calvin Nash, Robbie Henshaw, Bundee Aki, James Lowe, Jack Crowley, Jamison Gibson-Park; Andrew Porter, Dan Sheehan, Tadhg Furlong, Joe McCarthy, Tadhg Beirne, Peter O'Mahony, Josh van der Flier, Caealan Doris.
Replacements: Ronan Kelleher, Cian Healy, Oli Jager, James Ryan Ryan Baird, Jack Conan, Conor Murray, Stuart McCloskey.
Wales: Cameron Winnett, Josh Adams, George North, Nick Tompkins, Rio Dyer, Sam Costelow, Tomos Williams; Gareth Thomas, Elliot Dee, Keiron Assiratti, Dafydd Jenkins, Adam Beard, Alex Mann, Tommy Reffell, Aaron Wainwright.
Replacements: Ryan Elias, Corey Domachowski, Dillon Lewis, Will Rowlands, Mackenzie Martin, Kieran Hardy, Ioan Lloyd, Mason Grady.
Scotland vs. England, Saturday 4.45pm, Murrayfield, Edinburgh
Scotland fullback Blair Kinghorn and wing Kyle Steyn return to Gregor Townsend's lineup, providing a significant boost to a backline marshalled by mercurial fly-half Finn Russell.
Kinghorn missed their first two championship games -- a narrow win in Wales and controversial home loss to France -- with a knee injury, forcing Townsend to play regular wing Kyle Rowe and uncapped Harry Paterson at No. 15.
Steyn pulled out of the match against France on the day after his wife went into labour, and will partner fellow wing Duhan van der Merwe and Kinghorn in a potent back three that will provide plenty of threat to the visitors.
Sione Tuipulotu and Huw Jones continue their midfield partnership, while co-captain Russell is alongside scrum-half Ben White, who has been in outstanding form this season.
There is one switch in the forwards as former skipper Jamie Ritchie returns to the side of the scrum. He forms a back row with co-captain Rory Darge and No. 8 Jack Dempsey.
Meanwhile, England coach Steve Borthwick has made five changes to the side that beat Wales in Round 2. Danny Care gets his first Six Nations start in six years at scrum-half in place of the injured Alex Mitchell.
Ollie Lawrence returns from a hip injury that kept him out of the first two games to add some power to the midfield, where he'll start alongside Henry Slade.
In the forwards, Dan Cole and Ellis Genge will start at prop, replacing Will Stuart and Joe Marler, respectively.
In a surprise selection, George Furbank replaces Freddie Steward at fullback. Steward was available for selection but has been left out of the matchday squad.
Scotland: Blair Kinghorn, Kyle Steyn, Huw Jones, Sione Tuipulotu, Duhan van der Merwe, Finn Russell, Ben White; Pierre Schoeman, George Turner, Zander Fagerson, Grant Gilchrist, Scott Cummings, Jamie Ritchie, Rory Darge, Jack Dempsey.
Replacements: Ewan Ashman, Alec Hepburn, Elliot Millar-Mills, Sam Skinner, Andy Christie, George Horne, Ben Healy, Cameron Redpath.
England: George Furbank, Tommy Freeman, Henry Slade, Ollie Lawrence, Elliot Daly, George Ford, Danny Care; Ellis Genge, Jamie George, Dan Cole, Maro Itoje, Ollie Chessum, Ethan Roots, Sam Underhill, Ben Earl
Replacements: Theo Dan, Joe Marler, Will Stuart, George Martin, Chandler Cunningham-South, Ben Spencer, Fin Smith, Immanuel Feyi-Waboso
France vs. Italy, Sunday 3pm, Stade Pierre-Mauroy, Villeneuve-d'Ascq
France named 19-year-old lock Posolo Tuilagi in their starting lineup for the first time and confirmed Charles Ollivon as captain.
Tuilagi -- nephew to England centre Manu Tuilagi -- came off the bench in France's opening two matches of this year's championship, but now partners Cameron Woki in the second-row.
He is one of two changes named on Friday by coach Fabien Galthie to the French side that edged Scotland in a controversial 20-16 win at Murrayfield almost two weeks ago.
Ollivon takes over the leadership from Gregory Alldritt, who suffered a cut to his left thigh against the Scots and sits out.
Alldritt's absence also means a reshuffle in the back row as Francois Cross moves to No. 8 and Paul Boudehent comes in on the side of the pack.
Meanwhile, Ross Vintcent will make a first start for Italy as head coach Gonzalo Quesada also named his team on Friday.
The South African-born 21-year-old, who qualifies for Italy through his maternal grandfather, came off the bench to earn his first cap in the 36-0 defeat to Ireland earlier this month, and starts against France at No. 8.
Quesada has made six changes from the side which lost in Dublin, while Riccardo Favretto will also make his first start, replacing flanker Alessandro Izekor.
Favretto's only previous cap came off the bench in 2021.
"We want to show the best version of ourselves. We have heart, character and determination," Quesada said in a statement. "All these characteristics must be put on the field against a team that is tactically and physically strong."
France: Thomas Ramos, Damian Penaud, Gael Fickou, Jonathan Danty, Louis Bielle-Biarrey, Matthieu Jalibert, Maxime Lucu, Francois Cros, Charles Ollivon, Paul Boudehent, Posolo Tuilagi, Cameron Woki, Uini Atonio, Peato Mauvaka Cyril Baille.
Replacements: Julien Marchand, Sebastien Taofifenua, Dorian Aldegheri, Romain Taofifenua, Alexandre Roumat, Esteban Abadie, Nolann Le Garrec, Yoram Moefana.
Italy: Ange Capuozzo, Tommaso Menoncello, Ignacio Brex, Federico Mori, Monty Ioane, Paolo Garbisi, Martin Page-Relo, Ross Vintcent, Michele Lamaro, Riccardo Favretto, Federico Ruzza, Niccolo Cannone, Giosue Zilocchi, Giacomo Nicotera, Danilo Fischetti.
Replacements: Gianmarco Lucchesi, Mirco Spagnolo, Simone Ferrari, Matteo Canali, Andrea Zambonin, Manuel Zuliani, Stephen Varney, Leonardo Marin.