Irish rugby great Ronan O'Gara landed his second late drop-goal in successive European Cup games to give two-time champions Munster a 27-24 victory over Castres on Saturday.

The 34-year-old flyhalf, who had given Munster the win over last season's finalists Northampton with a drop goal in the fourth minute of time added-on last weekend, landed the decisive kick from 30 yards out to deprive a valiant Castres side of a share of the points.

O'Gara's heroics in his 99th European Cup appearance sees Munster go second in the group a point beihnd Welsh side Scarlets, who beat Northampton on Friday, and set things up nicely for their double header next month.

"The lads set me up perfectly for the drop goal," said O'Gara. "I am happy for the squad and to have played my part in it."

Elsewhere Harlequins superb start to the season continued as they outclassed Gloucester 28-9 to take their winning streak to 12 and their best ever run since the game turned professional.

Munster came off worst in the opening quarter of their match trailing Castres 11-0 including an early try by hooker Brice Mach.

Mach, though, was to go off later in the half adding to the hosts injury worries as international wing Marc Andreu had been taken off with what turned out to be a serious ankle injury which will see him sidelined for up to three months.

Munster fought their way back into the match and 33-year-old former All Black Doug Howlett went over in the 23rd minute. O'Gara converted to make it 11-7.

Castres refreshing attacking style was rattling Munster and it paid off in the 37th minute as a nicely-worked passing move saw Pierre-Gilles Lakafia step inside Howlett and touch down - Pierre Bernard converted.

O'Gara, though, added a penalty in time added-on to send them in 18-10 down at the break.

Things looked even brighter for the Irish province four minutes into the second-half as Peter O'Mahony ran in to touch down from 25 yards out and with O'Gara adding the conversion there was just a point in it.

Bernard eased the pressure on the hosts with a penalty as Munster kept on making uncharacteristic errors, but O'Gara then created their third try as he blocked Remy Tales's clearing kick, the ball bounced into Denis Leamy's arms and he offloaded for Will Chambers to touch down.

O'Gara added a superb conversion to make it 24-21 to Munster with 12 minutes remaining but they were all square with 10 minutes to go as Bernard added another penalty and it needed O'Gara's intervention to settle matters.

Bernard sportingly hugged O'Gara at the end and paid a fulsome tribute to him.

"O'Gara is a world class player and he made the difference this evening just as he knew how to do so last Saturday," he said.

Earlier Matthew Morgan hit a long-range penalty with 10 seconds remaining to help Ospreys claim a dramatic 26-26 draw with Italian club Treviso.

Treviso outscored the Welsh region by three tries to two and will be disappointed not to have come away with a rare victory at continental level.

The hosts scored through prop Michele Rizzo, wing Benjamin da Jager and scrumhalf Tobias Botes with international flyhalf Kristopher Burton kicking 11 points.

Tommy Bowe and Ryan Jones scored Ospreys tries, Dan Biggar booting 13 points before the 19-year-old Morgan added his late penalty.

In the same Pool, twice beaten finalists Biarritz posted a 15-10 victory - only their second win in all competitions this season - over English champions Saracens thanks to tries from France No.8 Imanol Harinordoquy and Zimbabwe-born US wing Takudzwa Ngwenya.

Victory came as a welcome relief for Biarritz director of rugby Patrice Lagisquet.

"At last a win at Aguilera (their home ground) and what a victory because we have beaten the English champions, who are an exceptional team," said Lagisquet.

Saturday's scores and scorers:

Gloucester 9-28 Harlequins

The scorers:

For Gloucester:
Pens: Burns 3

For Harlequins:
Tries: Brown, Hopper, Easter
Cons: Evans 2
Pens: Evans 3

The teams:

Gloucester: 15 Jonny May, 14 Charlie Sharples, 13 Henry Trinder, 12 Mike Tindall, 11 Lesley Vainikolo, 10 Freddie Burns, 9 Rory Lawson,8 Alasdair Strokosch. 7 Akapusi Qera, 6 Peter Buxton, 5 Jim Hamilton, 4 Will James, 3 Rupert Harden, 2 Scott Lawson, 1 Nick Wood.
Replacements: 16 Darren Dawidiuk, 17 Dan Murphy, 18 Dario Chistolini, 19 Tom Savage, 20 Luke Narraway, 21 Dave Lewis, 22 Tim Taylor, 23 Tom Voyce.

Harlequins: 15 Mike Brown, 14 Seb Stegmann, 13 Matt Hopper, 12 Jordan Turner-Hall, 11 Sam Smith, 10 Nick Evans, 9 Karl Dickson,8 Nick Easter. 7 Chris Robshaw, 6 Maurie Faasavalu, 5 George Robson, 4 Tomas Vallejos, 3 James Johnston, 2 Joe Gray, 1 Joe Marler.
Replacements: 16 Chris Brooker, 17 Nic Mayhew, 18 Tim Fairbrother, 19 Charlie Matthews, 20 Luke Wallace, 21 Danny Care, 22 Rory Clegg, 23 Tom Casson.

Referee: Christophe Berdos (France)

The scorers:

For Connacht:

For Toulouse:

The teams:

Connacht: 15 Gavin Duffy, 14 Tiernan O'Halloran, 13 Eoin Griffin, 12 Dave McSharry, 11 Brian Tuohy, 10 Miah Nikor, 9 Paul O'Donohoe, 8 George Naoupu, 7 John Muldoon, 6 Mike McCarthy, 5 Dave Gannon, 4 Michael Swift, 3 Rodney Ah You, 2 Adrian Flavin, 1 Brett Wilkinson.
Replacements: 16 Ethienne Reynecke, 17 Ronan Loughney, 18 Dylan Rogers, 19 TJ Anderson, 20 Ray Ofisa, 21 Frank Murphy, 22 Niall O'Connor, 23 Henry Fa'afili.

Toulouse: 15 Clément Poitrenaud, 14 Maxime Medard, 13 Florian Fritz, 12 Yannick Jauzion, 11 Vincent Clerc, 10 Lionel Beauxis, 9 Luke Burgess, 8 Louis Picamoles , 7 Thierry Dusautoir, 6 Jean Bouilhou, 5 Yoann Maestri, 4 Grégory Lamboley, 3 Census Johnston, 2 William Servat, 1 Yohan Montes.
Replacements: 16 Gary Botha, 17 Jean-Baptiste Poux, 18 Johnson Falefa, 19 Romain Millo-Chluski, 20 Nicolas Vergallo, 21 Yannick Nyanga, 22 Luke McAlister, 23 Gillian Galan.

Referee: Greg Garner (England)

Castres 24-27 Munster

The scorers:

For Castres:
Tries: Mach, Lakafia
Con: Bernard
Pens: Bernard 4

For Munster:
Tries: Howlett, O'Mahony, Chambers
Cons: O'Gara 3
Pen: O'Gara
DG: O'Gara

The teams:

Castres: 15 Florian Denos, 14 Max Evans, 13 Paul Bonnefond, 12 Pierre-Manuel Garcia, 11 Marc Andreu, 10 Pierre Bernard, 9 Thierry Lacrampe, 8 Chris Masoe, 7 Yannick Caballero, 6 Jannie Bornman, 5 Iosefa Tekori, 4 Scott Murray, 3 Karena Wihongi, 2 Brice Mach, 1 Anton Peikrishvili.
Replacements: 16 Mathieu Bonello, 17 Michaël Coetzee, 18 Luc Ducalcon, 19 Matthias Rolland, 20 Rodrigo Capo Ortega, 21 Romain Teulet, 22 Rémi Tales, 23 Pierre-Gilles Lakafia.

Munster: 15 Johne Murphy, 14 Doug Howlett, 13 Danny Barnes, 12 Lifeimi Mafi, 11 Denis Hurley, 10 Ronan O'Gara, 9 Conor Murray, 8 James Coughlan, 7 Niall Ronan, 6 Peter O'Mahony, 5 Paul O'Connell, 4 Donnacha Ryan, 3 BJ Botha, 2 Damien Varley, 1 Wian du Preez.
Replacements: 16 Denis Fogarty, 17 Marcus Horan, 18 John Hayes, 19 Donncha O'Callaghan, 20 Denis Leamy, 21 Tomas O'Leary, 22 Ian Keatley, 23 Will Chambers.

Referee: Wayne Barnes (England)

Leicester 20-9 Ulster

The scorers:

For Leicester:
Try: Smith
Pens: Flood 5

For Ulster:
Pen: Humphreys 3

The teams:

Leicester: 15 Geordan Murphy, 14 Horacio Agulla, 13 Matt Smith, 12 Andy Forsyth, 11 Alesana Tuilagi, 10 Toby Flood, 9 Sam Harrison, 8 Thomas Waldrom, 7 Jules Salvi, 6 Tom Croft, 5 Geoff Parling, 4 Louis Deacon, 3 Dan Cole, 2 George Chuter, 1 Marcos Ayerza.
Replacements: 16 Rob Hawkins, 17 Boris Stankovich, 18 Martin Castrogiovanni, 19 George Skivington, 20 Steve Mafi, 21 Ben Youngs, 22 Jeremy Staunton, 23 Niall Morris.

Ulster: 15 Simon Danielli, 14 Andrew Trimble, 13 Darren Cave, 12 Nevin Spence, 11 Craig Gilroy, 10 Ian Humphreys, 9 Paul Marshall, 8 Pedrie Wannenburg, 7 Chris Henry, 6 Stephen Ferris, 5 Dan Tuohy, 4 Johann Muller, 3 Declan Fitzpatrick, 2 Rory Best, 1 Tom Court.
Replacements: 16 Nigel Brady, 17 Paddy McAllister, 18 Adam Macklin, 19 Lewis Stevenson, 20 Willie Faloon, 21 Ian Porter, 22 Paddy Jackson, 23 Adam D'Arcy.

Referee: Romain Poite (France)

Biarritz 15-10 Saracens

The scorers:

For Biarritz:
Tries: Harinordoquy, Ngwenya
Con: Peyrelongue
Pen: Peyrelongue

For Saracens:
Try: Goode
Con: Farrell
Pen: Farrell

The teams:

Biarritz Olympique: 15 Dane Haylett-Petty, 14 Taku Ngwenya, 13 Benoît Baby, 12 Damien Traille, 11 Iain Balshaw, 10 Marcelo Bosch, 9 Luix Roussarie, 8 Raphael Lakafia, 7 Imanol Harinordoquy, 6 Benoit Guyot, 5 Erik Lund, 4 Jérôme Thion, 3 Sylvain Marconnet, 2 Benoit August, 1 Fabien Barcella.
Replacements: 16 Arnaud Heguy, 17 Yvan Watremez, 18 Francisco Gomez Kodela, 19 Pelu Taele, 20 Florian Faure, 21 Yann Lesgourgues, 22 Julien Peyrelongue, 23 Ilikena Bolakoro.

Saracens: 15 Chris Wyles, 14 David Strettle, 13 Owen Farrell, 12 Brad Barritt, 11 James Short, 10 Charlie Hodgson, 9 Ben Spencer, 8 Ernst Joubert, 7 Jacques Burger, 6 Kelly Brown, 5 Hayden Smith, 4 Steve Borthwick, 3 Matt Stevens, 2 John Smit, 1 Rhys Gill.
Replacements: 16 Jamie George, 17 Deon Carstens, 18 Carlos Nieto, 19 Mouritz Botha, 20 Andy Saull, 21 Luke Baldwin, 22 Adam Powell, 23 Alex Goode.

Referee: Nigel Owens (Wales)
Assistant referees: Leo Colgan (Ireland), Richard Kerr (Ireland)

Treviso 26-26

The scorers:

For Treviso:
Tries: Rizzo, de Jager, Botes
Con: Burton
Pens: Burton 3

For Ospreys:
Tries: Bowe, Jones
Cons: Biggar 2
Pens: Biggar 3, Morgan

The teams:

Treviso: 15 Ludovico Nitoglia, 14 Benjamin de Jager, 13 Tommaso Benvenuti, 12 Alberto Sgarbi, 11 Brendan Williams, 10 Kristopher Burton, 9 Tobias Botes, 8 Robert Barbieri, 7 Alessandro Zanni, 6 Benjamin Vermaak, 5 Cornelius van Zyl, 4 Antonio Pavanello, 3 Lorenzo Cittadini, 2 Enrico Ceccato, 1 Michele Rizzo.
Replacements: 16 Franco Sbaraglini, 17 Ignacio Fernandez Rouyet, 18 Pedro di Santo, 19 Valerio Bernabo, 20 Gonzalo Padrò, 21 Manoa Vosawai, 22 Willem de Waal, 23Fabio Semenzato.

Ospreys: 15 Richard Fussell, 14 Tommy Bowe, 13 Andrew Bishop, 12 Ashley Beck, 11 Shane Williams, 10 Dan Biggar, 9 Kahn Fotualii, 8 Jonathan Thomas, 7 Justin Tipuric, 6 George Stowers, 5 Ian Evans, 4 Ryan Jones, 3 Adam Jones, 2 Richard Hibbard, 1 Duncan Jones.
Replacements: 16 Mefin Davies, 17 Ryan Bevington, 18 Aaron Jarvis, 19 Ian Gough, 20 Joe Bearman, 21 Rhys Webb, 22 Matthew Morgan, 23 Tom Isaacs.

Referee: Pascal Gauzere (France)