Munster will hope that last weekend's 18-13 win over Treviso is the first of four victories over the Italians this season, with the pair due to clash on the opening weekend of the Champions Cup in November.
Treviso will entertain Edinburgh this weekend when they will hope to get their season up and running, despite having eight players away on World Cup duty.
Top 14 champions Slade Francais will also hope to spark their campaign after falling to a second loss in a row.
Toulon had lost their opening two games and the European champions were also going to produce something special in Paris and Paul O'Connell's new club duly obliged in a 20-13 win.
Stade Francais looked good for victory when they led 13-10 at the interval but they were held scoreless after the restart.
Jonathan Pelissie kicked a couple of penalties to edge Toulon in front and when Stade weren't able to respond, Bernard Laporte's side scored a late try to inflict a surprise home defeat on the Top 14 holders.
Stade Francais will hope to bounce back but face a tricky trip to Montpellier tomorrow.
Meanwhile, a crowd of over 8,000 saw Leicester Tigers take on Argentina in a friendly at Welford Road, with the Pumas running out 55-34 winners.
Argentina, in their final warm-up game before the World Cup, led 38-13 early in the second half before Leicester hit back and cut the gap at one stage to four points before the Pumas pulled away again in the final 10 minutes.