Three law variations covering red card replacements, captain's challenge and goal-line drop-outs will be used in the inaugural Guinness PRO14 Rainbow Cup.
Curtis Rona's last-gasp try stole 14-man London Irish a dramatic 41-35 victory over Cardiff Blues, while Bath beat Zebre and Glasgow lost to Montpellier.
A round-up of Saturday's PRO14 action as Leinster ended Ulster's push for a place in the final, while Dragons and Glasgow also picked up wins.
Adam Hastings' Scotland return will be further delayed after he was handed a three-game ban for his red card against Leinster on Sunday.
A clinical display from Ulster ensured they kept the pressure on Leinster thanks to a 19-13 victory over Glasgow.
Wales wing Louis Rees-Zammit is among the Six Nations stars in club action on Friday night as focus shifts back to the Premiership and PRO14.
With the form of Duhan van der Merwe and Jamie Ritchie, and the return of the brilliant Finn Russell, will Scotland win their first Six Nations title this year?
Fiji international Leone Nakarawa will join Ulster from PRO14 rivals Glasgow Warriors at the end of the season.
A passing train helped Glasgow get back on track as they climbed off the bottom of their PRO14 conference with a 23-22 win over Edinburgh.
We take a look at where European rugby can go next, after the Champions Cup's temporary suspension was confirmed on Monday.
Glasgow Warriors' PRO14 match against Edinburgh has been postponed shortly before kick-off due to a frozen pitch at Scotstoun.
Connacht won in Dublin for the first time since September 2002, while Ulster maintained their 100-per-cent start in the PRO14 by beating Munster.
Glasgow and Edinburgh's postponed PRO14 derby clash rescheduled in a bid to reduce the risk of spreading Covid-19
Glasgow have been forced to call off next week’s clash with Edinburgh after reporting four players have tested positive for coronavirus.
Exeter and Glasgow Warriors' Champions Cup fixtures have been cancelled after a number of Chiefs players and staff tested positive for Covid-19.
Danny Cipriani has left Gloucester with immediate effect, with the club announcing Scotland fly-half Adam Hastings will join for next season.
Exeter launched their defence of the Heineken Champions Cup by thrashing Glasgow 42-0 at Sandy Park.
Gloucester conceded the most points in their Champions Cup history as they started the new campaign with a 55-10 hammering at the hands of Lyon.
Ahead of Sunday's four Heineken Champions Cup clashes, we take a look at each club's form, team news and key players...
Glasgow fly-half Brandon Thomson missed a simple conversion with the final kick to hand Dragons a dramatic 23-22 victory at Scotstoun.