Edinburgh, Newport Gwent Dragons and Sale Sharks all triumphed in Friday's Challenge Cup matches.
Edinburgh 23-0 Agen
Edinburgh nilled Agen and secured a try bonus point in an impressive win over their Top 14 visitors.
A Greig Tonks penalty and Magnus Bradbury try were the only points of the first half as Edinburgh took an 8-0 advantage into the break.
It was from Mike Coman's 59th minute score however for Edinburgh put the result beyond doubt.
Tonks and Watson followed him over to put Edinburgh top of Pool 5 ahead of Irish's game with Grenoble.
Tries: Bradbury, Coman, Tonks, Watson
Edinburgh: 15 Jack Cuthbert, 14 Damien Hoyland, 13 Michael Allen, 12 Andries Strauss, 11 Will Helu, 10 Greig Tonks, 9 Sean Kennedy, 8 Magnus Bradbury, 7 Hamish Watson, 6 Jamie Ritchie, 5 Ben Toolis, 4 Alex Toolis, 3 John Andress, 2 Stuart McInally (c), 1 Rory Sutherland
Replacements: 16 Neil Cochrane, 17 Allan Dell, 18 Simon Berghan, 19 Anton Bresler, 20 Mike Coman, 21 Nathan Fowles, 22 Chris Dean, 23 Dougie Fife
Agen: 15 Benoit Sicart, 14 François Tardieu, 13 Vincent Roux, 12 Pierre Fouyssac, 11 Filipo Nakosi, 10 François Bouvier, 9 Paul Abadie, 8 Marc Baget, 7 Denis Marchois, 6 Sione Tau, 5 Corentin Braendlin, 4 Léo Bastien, 3 Nicolas Chocou, 2 Marc Barthomeuf, 1 Quentin Bethune
Replacements: 16 Florian Dufour, 17 Viliamu Afatia, 18 , 19 Felicien Vergnon, 20 Nicolas Gal, 21 Baptiste Cadiou, 22 Clement Darbo, 23 Alban Conduche
Referee: Ian Davies (Wales)
Assistant Referees: Rhys Thomas (Wales), Simon Rees (Wales)
Dragons 31-18 Castres
An impressive bonus point win from the Dragons moved the Welsh region to the top of Pool 2 in the Challenge Cup.
Hallam Amos, in his first game back since being injured for Wales at the Rugby World Cup, scored in the first minute and was followed over by Nic Cudd and Lewis Evans before half-time.
David Smith's converted try into injury time at the end of the first half gave Castres a slim lifeline.
Followed up by a try from Christophe Samson, Castres were right back in the hunt. But a red card for Alexandre Bias swung the game back in the Dragons' favour.
Ashton Hewitt's converted try in the 72nd minute wrapped up an impressive win.
Tries: Amos, Cudd, Evans, Hewitt
Cons: Tovey 4
Tries: D Smith, Samson
Pens: Palis 2
Yellow Card: Sione
Red Card: Bias
Dragons: 15 Carl Meyer, 14 Ashton Hewitt, 13 Adam Hughes, 12 Adam Warren, 11 Hallam Amos, 10 Jason Tovey, 9 Sarel Pretorius, 8 Taulupe Faletau, 7 Nic Cudd, 6 Lewis Evans, Rynard Landman (c), 4 Cory Hill, 3 Brok Harris, 2 Elliot Dee, 1 Phil Price
Replacements: 16 Thomas Rhys Thomas, 17 Boris Stankovich, 18 Shaun Knight, 19 Matthew Screech, 20 Ed Jackson, 21 Charlie Davies, 22 Angus O’Brien, 23 Nick Scott
Castres: 15 Geoffrey Palis, 14 Sitiveni Sivivatu, 13 Thomas Combezou, 12 Romain Cabannes, 11 David Smith, 10 Francois Fontaine, 9 Julien Seron, 8 Mathieu Babillot, 7 Ibrahim Diarra, 6 Yannick Caballero, 5 Benjamin Desroche, 4 Christophe Samson, 3 Lucas Martinez, 2 Marc-Antoine Rallier, 1 Saimone Taumoepeau
Replacements: 16 Julien Beziat, 17 Karena Wihongi, 18 Eric Sione, 19 Alexandre Bias, 20 Theo Hannoyer, 21 Rudi Wulf, 22 Rémi Lamerat, 23 Benjamin Urdapilleta
Referee: Peter Fitzgibbon (Ireland)
Assistant Referees: Kieran Barry (Ireland), Ken Imbusch (Ireland)
TMO: Dermot Moloney (Ireland)
Pau 3-27 Sale Sharks
Johnny Leota's late try secured a try bonus point win for Sale on the road at Pau. As a result Sale moved momentarily top of Pool 2 ahead of Newport Gwent Dragons.
Pau rested their top stars and only had a Samuel Marques penalty to show for their efforts in a one-sided loss.
Andrei Ostrikov opened the scoring in the first minute and was followed over by Sale backs Will Addison and Nev Edwards in the first half to put Sale in position for a huge win.
But it took nearly the whole second half for them to finally get that elusive fourth score, Leota delivering with a minute to spare.
Tries: Ostrikov, Edwards, Addison, Leota
Cons: Cipriani 2
Pau: 15 Charly Malie, 14 Marika Vunibaka, 13 Julien Fumat, 12 Pierre Dupouy, 11 Mathieu Acebes, 10 Brandon Fajardo, 9 Samuel Marques, 8 Brice Monzeglio, 7 Josefa Ulago Domolailai, 6 Giovanni Habel Kuffner, 5 Claude Dry, 4 Cameron Pierce, 3 Giorgi Natsarashvili, 2 Thomas Bianchin, 1 Geoffrey Moise
Replacements: 16 Mehdi Boundjema, 17 Julien Jacquot, 18 Juan Pablo Orlandi, 19 Sean Dougall, 20 Loic Bernad, 21 Thierry Lacrampe, 22 Watisoni Votu, 23 Romain Buros
Sale: 15 Mike Haley, 14 Tom Arscott, 13 Will Addison, 12 Johnny Leota, 11 Nev Edwards, 10 Danny Cipriani, 9 Chris Cusiter, 8 Josh Beaumont (c), 7 Magnus Lund, 6 Cameron Neild, 5 Andrei Ostrikov, 4 Bryn Evans, 3 Vadim Cobbles, 2 Tommy Taylor, 1 Ross Harrison
Replacements: 16 Neil Briggs, 17 James Flynn, 18 Ciaran Parker, 19 Jonathan Mills, 20 Mark Easter, 21 James Mitchell, 22 Joe Ford, 23 Mark Jennings
Referee: Gary Conway (Ireland)
Assistant Referees: Leo Colgan (Ireland), Paul Haycock (Ireland)