Racing continue to impress in Top 14
Racing 92 continue to keep pace with leaders Montpellier in the Top 14 and after a third win from four, Munster's Champions Cup rivals are bang in form.
A try from ex-Glasgow lock Leone Nakarawa helped Racing into a 22-3 interval lead, and after Virimi Vakatawa and Marc Andreu ran in two more, Oyonnax made no real impact on Racing who easily held on to win.
Tomorrow we'll see exactly what Racing are made of this season when they make the most daunting of trips to face champions Clermont at Stade Marcel Michelin.
Elsewhere, two former Munster players Dave Foley and Sean Dougall were on form for Pau last weekend as they delivered victory over another pool rival, Castres.
Castres were 13-6 ahead at half-time thanks to Alex Tulou's try, but two in reply from Watisoni Votu in the third quarter saw Pau run out 28-13 winners.
Castres face another tough away assignment this weekend in Lyon.
In the English Premiership, Leicester Tigers picked up their first win of the season with a 24-10 victory over Gloucester at Welford Road.
It was a blistering start that gave Tigers the win as Ben Youngs scored twice and Nick Malouf also score a third try in the 20th minute.
That 21-0 half-time lead proved plenty for Tigers, who closed out the game easily, to move up to ninth place. They will hope to make further progress up the table when they face Harlequins tomorrow.