Connacht’s Dominic Robertson-McCoy was shown a red card for appearing to stamp on the head of Josh van der Flier in a 20-3 defeat to Leinster.
Leinster trailed to Jack Carty’s third-minute penalty, but Garry Ringrose and Sean Cronin crossed in the second half before Robertson-McCoy was involved in an incident that could lead to a lengthy suspension.
The Connacht prop trod on prone Leinster star Van der Flier’s head and was dismissed 10 minutes from time, having only been on the pitch a matter of seconds.
While Leinster have a five-point advantage at Conference B’s summit, Glasgow Warriors are three points clear of the Ospreys at the top of Conference A.
The Warriors were 29-13 winners over the Dragons, Lee Jones scoring either side of the interval to set in motion a relatively comfortable triumph.
Sam Davies’ boot made the difference for the Ospreys as they required just a single Luke Morgan try to defeat Zebre 22-8.
Humbled last week, @GlasgowWarriors have come out fighting ??
— PRO14 RUGBY (@PRO14Official) September 29, 2018
Scarlets, runners-up last term, are Leinster’s nearest challengers in Conference B after winning big against Southern Kings.
Jonathan Davies scored two of eight tries in a 54-14 success, while Munster went one better with nine as they triumphed 64-7 over Ulster.
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