Munster head coach Anthony Foley described his side's 14-3 home triumph over Saracens in the European Rugby Champions Cup as a "satisfying result".
London Irish made it two wins from two in the Challenge Cup as they battled past Grenoble 25-15 at the Stade Lesdiguières.
Munster took control of European Rugby Champions Cup Pool 1 with a 14-3 victory over Saracens at Thomond Park.
Cardiff Blues visit minnows Rovigo on Saturday, where victory for the Welsh side would tighten their grip on Pool 1 ahead of back-to-back meetings with London Irish in December.
Exeter failed to get their European campaign off to a winning start after a late Bayonne try condemned them to a 30-24 loss in France six days ago.
Gloucester rugby director David Humphreys has braced his team for "a huge test" against European Challenge Cup opponents Oyonnax at Stade Charles-Mathon.
Jonny May has signed a new long-term contract with Gloucester.
Saturday sees four European Rugby Challenge Cup showdowns, with Cardiff, Exeter, Connacht and Gloucester all in action.
Kurtley Beale has been fined £24,500 by the Australian Rugby Union for a serious violation of the ARU code of conduct by sending an offensive text.
Despite both enduring losing starts to the campaign last weekend, Clermont Auvergne and Sale Sharks picked up losing bonus points which could prove crucial in the 'Pool of Death'.
Glasgow will aim to back up their emphatic win over Bath as coach Gregor Townsend returns to familiar stomping ground in Montpellier.
Three-time champions of Europe Leinster will aim to take control of Pool 2 on Sunday as they travel to France for a showdown with Castres.