Three things we learned from the Six Nations weekend

Ireland remained on course for a Six Nations Grand Slam with victory over Scotland, France enjoyed a record-breaking success against England and Wales returned to winning ways by defeating Italy.

AFP Sport looks at three things we learned from the fourth round of the Championship.

Ireland's resilience on show against Scotland

Ireland have been lauded for an impressive run of results that means they are now just 80 minutes away from what would be only the fourth Grand Slam in their history following a 22-7 win against Scotland at Murrayfield on Sunday.

But what was just as admirable about their latest victory was the resilience they demonstrated as Caelan Doris, Iain Henderson, Dan Sheehan, Garry Ringrose and Ronan Kelleher were all forced off injured before full-time in Edinburgh.

"It was immense," said Ireland coach Andy Farrell. "Obviously it wasn't champagne rugby all round.

"But in terms of character, fight and want for each other that's the best game I've ever been involved in," added the former dual code rugby international, with Ireland now looking to complete a clean sweep against an England team set to feature his son, Owen Farrell, in Dublin on March 18.

France's pack the equal of their backs

The quality of a France back division led by outstanding scrum-half Antoine Dupont was evident for all to see during a 14-match unbeaten run that only ended with a second-round defeat by Ireland last month.

But as with all their very best France teams, this edition of Les Bleus also boast a formidable pack.

Their  set-piece strength and skill was on show a during an utterly dominant 53-10 win at Twickenham on Saturday as they inflicted England's heaviest home defeat of all time.

Yet the way World Cup hosts France scored the first of their seven tries, with just two minutes on the clock, was also a brilliant example of how much more is expected of forwards in the modern game.

Back-row Charles Ollivon and lock Thibauld Flament, who both went on to score two tries apiece, combined well with ball in hand before wing Ethan Dumortier continued the attack prior to releasing full-back Thomas Ramos as England were caught cold in style.

Crowley frustrated by referee's calls

Kieran Crowley, like many an Italy coach before him, is discovering that the Azzurri rarely get the benefit of the doubt from referees.

Having played well in defeats by France and Ireland, the two leading teams in this tournament, Italy had high hopes of a win against a Wales side also looking for their first victory of this Six Nations.

A lack of composure once more cost Italy during a 29-17 loss in Rome on Saturday but former New Zealand full-back Crowley was understandably aggrieved by some of the decisions made by Australian referee Damon Murphy.

Wales outscored Italy four tries to two, but Crowley was convinced Italy should been awarded a penalty try with the score at 15-3 when Wales fly-half Owen Williams made a tackle from an offside position with the Azzurri poised to score.

Murphy said a ruck had not been formed and the ball was in general play.

"I probably should not have, but I tried to talk to them (the referees) at half-time," said Crowley. "I just couldn't believe we didn't get a penalty try.

"I also can't understand how a team (Wales) can be penalised 17 times and not be warned once. It's frustrating." Wales were, in fact, penalised 14 times.