Sale Sharks sack winger Tom Arscott after he allegedly leaked confidential team information to Bristol before their Premiership game.
New tackle laws may restrict opportunities for Pacific Island rugby players, according to former Samoa captain Dan Leo.
Listen to a BBC Radio 5 live special programme, which speaks to England coach Eddie Jones and top referee Wayne Barnes about the new rules.
Cardiff Blues sign South Africa lock Franco van der Merwe after three seasons with Ulster.
Audio & Video
Watch the BBC's Six Nations trail, where each country's arguments will be settled on the pitch.
How to get into rugby union
How to get into rugby union - into the thick of the 15-player game or try rugby sevens, which made its Olympic debut in 2016.
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Commentaries, clips and podcasts
Enjoy the best debate, analysis and interviews with BBC 5 live and World Service plus our rugby union commentary listings.
What's on BBC Sport this week
This week's sport on the BBC includes Australian Open tennis, Masters snooker, European rugby union and Ski Sunday.