Wales will go for the Guinness Six Nations title and a fifth Grand Slam when they face France in Paris on Saturday.
Wayne Pivac’s team have already secured the Triple Crown, and they are now chasing a second Six Nations clean sweep in three seasons.
Here, the PA news agency looks at one of the key individual battles – a juggernaut contest between centres Virimi Vakatawa and George North.
Debut: v Italy 2016
Height: 6′ 1″
Weight: 15st 5lbs
Points: 50 (10 tries)
New Zealand-born Vakatawa qualified to represent France in 2013, and although it was another three years before he made his Test debut, he established a fearsome reputation on the world sevens circuit as a devastating runner and prolific try-scorer. He transferred those qualities to the 15-a-side arena and has become an integral part of the French back division, mixing his raw pace with power and a brilliant off-loading game that makes him a handful for any opposition defence. Form and fitness permitting, he could be a star of the 2023 Rugby World Cup in France.
George North – Ospreys
Debut: v South Africa 2010
Height: 6′ 4″
Weight: 16st 5lbs
Points: 215 (43 tries)
North has been moved from wing, where he played the overwhelming majority of his international career, to outside centre this season by Pivac, and the results have proved impressive. A natural line-breaker and solid defensive presence, he continues to be a key Wales figure, and recently became the youngest person in rugby union history to win 100 caps for their country. North has scored 43 tries in the red shirt, and one touchdown against France would take him past Shane Williams’ mark of 22 for most touchdowns in the Six Nations by a Wales player.