Dave Kearney's hat-trick helped Leinster begin the defence of their Pro14 title with a win over Benetton Treviso.
Scotland's record appearance holder Ross Ford has confirmed his retirement ahead of plans to go into strength and conditioning coaching.
Edinburgh's Pro14 play-off hopes hang by a thread after a damaging home defeat to Ulster, who extended their own domestic season.
Edinburgh have confirmed that seven players will leave the club at the end of the Pro14 season, with Ross Ford among them.
Iliesa Ratuva Tavuyara touched down and Tommaso Allan converted with the last play of the game as Benetton Treviso held Leinster in Dublin.
Owen Farrell missed Saracens' Champions Cup win over Glasgow Warriors as his wife went into labour before kick-off.
Cardiff Blues used Wales Grand Slam heroes Gareth Anscombe and Josh Navidi from the start in their demolition of the Scarlets.
John Barclay will be looking to make up for lost time when he comes up against the European champions on Friday.
Wales international Leigh Halfpenny featured in the Scarlets' 10-6 win over Munster, while Glasgow Warriors went top of Conference A.
Luca Sperandio and Niccolo Cannone scored two tries apiece as Benetton Treviso stretched their unbeaten run to eight games.
Centre Stuart McCloskey celebrated a century of matches for Ulster by dotting down for the only try against the Ospreys.
Southern Kings produced a stunning late fightback to claim only their second win of the season, halting Edinburgh's impressive run.
Both Edinburgh and Glasgow Warriors are through to the European Champions Cup quarter-finals due to the former's 19-10 win over Montpellier.
All four Pro14 sides in European Rugby Champions Cup action on Saturday secured victories, three coming against French opposition.
Munster moved top of Pro14's Conference A after capitalising on Glasgow Warriors' defeat to in-form Benetton Treviso.
Munster ended a four-game losing streak against Leinster with a 26-17 triumph on Saturday, while Edinburgh retained the 1872 Cup.