Racing 92 ran out of time in their defeat to Toulouse, while La Rochelle survived a Top14 scare against lowly Grenoble.
Racing 92 have some pretty formidable back-up for Finn Russell with Dan Carter returning to the Top14 club.
A minor calf strain means Chris Ashton will miss England's trip to face Wales in the Six Nations.
Marnus Schoeman finished with a hat-trick in Buenos Aires on Saturday as the Lions started the 2019 campaign on a winning note.
In his first Super Rugby appearance, 29-year-old former sevens star Rosko Specman set the Bulls on the road to beating the Stormers 40-3.
Perpignan finally had a win to celebrate, while Clermont Auvergne were too good for Bordeaux-Begles in Top14.
Zebre put on a spirited showing but ultimately fell short against Pro14 heavyweights Leinster.
Leicester Tigers limped to defeat at Saracens, meaning the victors once again sit top of the Premiership.
New Zealand Conference giants the Crusaders and the Hurricanes each came through testing openers in Super Rugby on Saturday.
Leaders Exeter Chiefs suffered a third Premiership defeat of the season at Gloucester, while Wasps moved into the top four.
Centre Stuart McCloskey celebrated a century of matches for Ulster by dotting down for the only try against the Ospreys.
Following a head injury against Scotland, Johnny Sexton is fit again and in the running to play for Ireland in Italy.
Wales were dealt a blow on Friday as Leigh Halfpenny's expected comeback for the Scarlets did not come to fruition.
Sio Tomkinson's red card made a Highlanders comeback look unlikely, but Aaron Smith had other ideas and punished the Chiefs.
Eddie Jones sought to dismiss Wales' strong record in Cardiff ahead of England's Six Nations visit, but Neil Jenkins is not worried.
Owen Franks is looking forward to a new adventure in the Premiership after agreeing to join Northampton Saints.