Reigning champions Leinster start the defence of their RaboDirect PRO12 title with a trip to the Scarlets, one of three fixtures to take place on Friday night.
The Irish province will be hoping a trip to Llanelli is a good omen - they faced the same opponents last year in the opening round of matches and although they were beaten on that occasion, went on to be crowned champions.
That success last September was a rarity for the Scarlets; it was their first over Leinster in four years.
The hosts' hopes of a repeat are boosted by the availability of Rhys Priestland, meaning new signing Steve Shingler switches from fly-half to inside centre. Another new face, John Barclay, is not available, and Jon Davies is rested following his exertions for the British and Irish Lions.
Leinster, meanwhile, will hand a debut to fly-half Jimmy Gopperth while fellow new boy Mike McCarthy starts the game on the bench. Academy graduates Jack McGrath and Martin Moore are both named in the front-row.
Losing finalists Ulster also get their campaign underway in Wales, as they go up against the Dragons at Rodney Parade.
Visiting head coach Mark Anscombe makes just one alteration from the line-up selected for the pre-season friendly against Leicester last time out, selecting Paddy Jackson at fly-half.
Nick Williams was not available for selection as he's returned to New Zealand for family reasons, as Ulster look to get an opening win for the fourth straight season.
The Dragons have a new captain in place in Andrew Coombs and he leads a team that includes new faces Richie Rees, T. Rhys Thomas and Matthew Screech. Francisco Chaparro, Netani Talei and Kris Burton are amongst the list of replacements.
Elsewhere on Friday, Matthew Rees will captain Cardiff for the first time when the Blues travel to Glasgow to face the Warriors at Scotstoun Stadium.
The Wales hooker arrived from Scarlets in the summer and is named in the front row alongside Taufa'ao Filise and Scott Andrews for Cardiff, who have suffered defeat just once in their PRO12 opener since 2005.
However the Warriors will be hoping they can pick up from where they left off last season, having finished with seven straight victories in all competitions.
Skipper Al Kellock partners new Scotland cap Tim Swinson in the second row, with Scotland U20 captain Jonny Gray providing cover amongst the replacements. Jerry Yanuyanutawa starts his first game for the club at loosehead.
Ruaridh Jackson has been included on the bench, along with Chris Cusiter, who returned to action last weekend after an 11-month spell on the sidelines. The Warriors have lost just one of their last seven clashes with a Welsh region.