Matt Healy scorched in a hat-trick for Connacht and Jack Conan was man-of-the-match on his Leinster return.
Ireland are suffering from a rake of injuries to senior players at present. Joe Schmidt could yet make additions to his Six Nations squad and both Healy and Conan have done their cases no harm at all.
Healy ran in three tries in a 51-34 victory over Zebre in Italy.
The half century of points on the scoreboard ensured a bonus point win and also saw Connacht, back at the summit, reach 50 points for the season.
Leinster briefly went top of the table as they edged out Cardiff Blues by a single score.
In a match played in atrocious weather conditions, Jack Conan’s delayed pass and Isa Nacewa’s resulting try was the one moment of true class in the game.
Josh Navidi scored a late try for the hosts but it was not enough to prevent the Leinster win.