The Champions Cup is back after a five month absence as 20 teams from seven countries compete for European club rugby's coveted prize.
Saracens are looking to emulate the Toulon side of 2013-2015 in winning a third Champions Cup in a row, while La Rochelle make their debut in the top flight.
The first round gets underway on Friday at the Kingspan with Ulster hosting Wasps as Charles Piutau lines up against his former club.
Get all the team news below and keep abreast of the action with ESPN.
Kingspan, 7.45 p.m.
British & Irish Lions flanker Iain Henderson will captain Ulster for the first time as Les Kiss names a starting XV that features 12 internationals.
Kiss has made three personnel changes from their win over Connacht in the PRO14, with Henderson shifting to the second row while Robbie Diack and Sean Reidy come in at blindside and openside respectively. In the backline, Louis Ludik earns selection on the right wing while Christain Lealiifano will make his European debut from fly-half. Rory Best remains out injured.
Wasps are bolstered by the return of captain Joe Launchbury as well as England back row Nathan Hughes and fly-half Jimmy Gopperth. Christain Wade has been recalled on the right wing as has Dan Robson at scrum-half.
England's Elliot Daly and James Haskell also start, while Springboks star Willie le Roux will wear the No. 15 jersey.
RDS Arena, 1 p.m.
Leinster welcome back Isa Nacewa from injury to the starting line-up and he takes his place in the midfield. Joey Carbery takes his spot at fullback for the fifth time this season while Adam Byrne also makes his fifth start on the wing. Barry Daly starts on the opposite flank and is set to make his European debut.
Elsewhere for Leinster, Ross Byrne starts instead of the injured Johnny Sexton.
Montpellier have made two forward changes from the side's 31-10 loss to Stade Francais Paris on Oct. 7 with Louis Picamoles and Yacouba Camara coming in for Julien Bardy and Fulgence Ouedraogo.
Francois Steyn takes up the inside centre berth with and is partnered with Joseph Tomane who starts at No. 13. Thomas Darmon starts with Aaron Cruden out injured.
Stade Yves Du Manoir, 3.15 p.m.
Graham Kitchener returns to the Tigers starting XV after recovering from injury and he's joined by Telusa Veainu and Ben Youngs who also return after withdrawal from the match last week against London Irish due to illness.
Nick Malouf is selected to make his European Cup debut and Ben White is also included included in the squad after Sam Harrison's withdrawal against London Irish. Brendon O'Connor also returns from a hamstring injury.
Racing 92 have made six changes to the starting XV that lost 16-9 to La Rochelle last time out. Dimitri Szarzewski replaces Camille Chat as hooker while the only other replacement to the forwards is Wenceslas Lauret coming in for So'otala Fa'aso'o.
Racing 92 are without mercurial fly-half Dan Carter.
Twickenham Stoop, 5.30 p.m.
Director of Rugby John Kingston has made just three alterations to the starting lineup which emerged from last week's encounter with Sale as 42-26 winners. Mike Brown's return at fullback represents the only change to the backline, as the England international replaces Aaron Morris. In the forwards, James Horwill is reintroduced following his recovery from concussion as Ben Glynn is moved to blindside flanker as a replacement for the injured Jack Clifford.
Jason Eaton starts at lock to captain a La Rochelle side which recorded an impressive 16-9 win over Racing 92 in their last outing. Former Aviva Premiership veteran Ryan Lamb starts the game at fly-half, with Alexi Bales hoping to continue his impressive kicking from the weekend in the No. 9 jersey.
The Recreation Ground, 5.30 p.m.
Fresh from their 29-13 win over Worcester at the Rec last Saturday, Todd Blackadder has made five changes to his Bath side for their first Champions Cup fixture against Benetton. The most notable is the inclusion of Josh Lewis, who makes his first start at fly-half after coming off the bench last weekend. He is joined in the backs by Max Clark, who comes in for Ben Tapuai, while Nick Auterac, Tom Dunn and Luke Charteris are all drafted into the pack.
They face a Benetton side which has won three of their first six games in the PRO14. Despite last weekend's 31-3 triumph over Southern Kings, Benetton have ringed in the chances for their trip to the Rec, with Luca Sperandio replacing Jayden Hayward at fullback. Sperandio is joined in the backs by Tommaso Benvenuti, Ian McKinley and Giorgio Bronzini, who will start at 11, 10 and 9 respectively.
Sandy Park, 7.45 p.m.
For the Chiefs, Phil Dolman is set to start at fullback, replacing the injured Jack Nowell after the England international was forced off in their side's Premiership clash with Newcastle Falcons last week.
Ben Moon replaces Carl Rimmer in the front row with Dave Dennis also destined to sit out the Champions Cup clash after suffering a training injury. Julian Salvi starts along with Don Armond with Thomas Waldrom also returning to the squad having recovered from a broken foot in preseason.
Glasgow have made two changes to the starting XV which beat Cheetahs last time out. Peter Horne starts at inside centre with Lee Jones coming in on the wing. Ali Price and Finn Russell combine at scrum-half and fly-half. George Turner makes his Champions Cup debut in an unchanged forward pack.
Winger Rory Hughes will not feature for the Warriors after undergoing surgery on his shoulder which has ruled him out for four to six months.
Stade Pierre-Fabre, 1 p.m.
Castres have won just one of their last five games and despite a close game against Brive last weekend which eventually ended in 27-22 defeat, they have still decided to make wholesale changes.
Rodrigo Capo Ortega comes in for Victor Moreaux while Yannick Caballero and Steve Mafi are also preferred in the back row. Elsewhere, Rory Kockott replaces Ludovic Radosavljevic at scrum-half. Taylor Paris also replaces Julien Caminati on the wing.
Munster have made five changes to their starting XV that played against Leinster last time out, with Simon Zebo, Rory Scannell, Stephen Archer, Darren Sweetnam and Mark Flanagan all coming in. Chris Farrell and Flanagan are making their Champions Cup debut on the trip to Stade Pierre-Fabre.
Stade Mayol, 3.15 p.m.
Champions Cup record try scorer Chris Ashton makes his European debut for Toulon while Mathieu Bastareaud -- who caused havoc when these sides met in Toulon in last season's competition -- captains the side, partnering Ma'a Nonu at centre.
Scarlets' Leigh Halfpenny makes his much awaited return to Toulon after his controversial departure from the French side last season. The fullback has overcome a hamstring problem to be fit to start. Johnny McNicoll moves from fullback to wing to facilitate the Wales and Lions player's return. Scott Williams also returns to Wayne Pivac's starting XV -- he captains the side.
Franklin's Gardens, 5.30 p.m.
Northampton have made three changes to their starting XV as they look to bounce back from last week's loss at Gloucester. September's Aviva Premiership Player of the Month Courtney Lawes returns to start at blindside flanker. There are also returns for Stephen Myler and Ben Foden at 10 and 11 after both players started last week's defeat on the bench. Elsewhere, Tom Wood could make his 150th appearance for the club from the bench.
Saracens are seeking their third consecutive European Champions Cup title and will be hoping to get their defence off to a winning start against their domestic rivals. Mark McCall has made just two changes to the side which dismantled Wasps on Sunday, with England international Owen Farrell recovering from a calf strain to return at fly-half. Meanwhile, Vincent Koch comes into the front row to partner Mako Vunipola and Jamie George, who scored a hat-trick in his last outing.
Liberty Stadium, 5.30 p.m.
Ospreys have made five changes for their Champions Cup opener. In the backs, Keelan Giles replaces Jeffrey Hassler to earn his first ever Champions Cup appearance while James Hook makes way for Owen Watkin in the centres. Dmitri Arhip comes into the front row in place of Ma'afu Fia in a pack which also sees Justin Tipuric and Dan Baker included in the back row at the expense of Olly Cracknell and James King.
Clermont travel to Wales sitting at ninth place in the French Top 14 after a difficult start. Following last week's 28-18 defeat to Toulouse, Frank Azéma has elected to make six changes for the Champions Cup tie. Alivereti Raka returns to the starting lineup as Nick Abendanon and Wesley Fofana miss out due to injury. Elsewhere, former Saracens player David Strettle earns a place on the wing as Morgan Parra prepares to make his 200th appearance for the club.