Munster produced a gutsy defensive display to hold out for a Heineken Champions Cup victory over Northampton Saints at Franklin's Gardens.

The Irish province picked up three yellow cards as they were pinned back by the hosts during a scoreless second half.

But despite dominating possession in the second period, Saints were unable to breach a heroic Munster defence.

With both sides aiming to bounce back from defeats last week, Northampton's plans were disrupted when England lock Courtney Lawes was forced to withdraw shortly before kick-off, having been named to start his first match since September following a head injury.

Without Lawes, Northampton found themselves under pressure early on and Munster were rewarded in the 14th minute when Coombes forced his way over the line from close range after his first score was ruled out for offside.

Saints responded well and got on the scoreboard through a Fin Smith penalty before an offside allowed Joey Carbery to kick Munster's first penalty.

And while Smith slotted a second penalty between the posts after Carbery's foul on George Furbank, Munster extended their advantage when Coombes touched down for the second time four minutes before the break.

From a Munster line-out, Coombes collected a Tadhg Beirne pass and squeezed through the Northampton bodies on the line before Carbery's conversion handed Graham Rowntree's side an 11-point halfway lead.

With Saints chasing the game, tempers frayed after the restart when a mass brawl involving numerous players resulted in yellow cards for Jack O'Donoghue and Lewis Ludlam.

Munster were then reduced to 13 players when Craig Casey was sin-binned for a high tackle on James Raam, but referee Pierre-Baptiste Nuchy did not award Saints a penalty try.

Carbery also saw yellow for Munster, but despite spending large spells inside the Irish side's 22, Northampton were unable to make their numerical advantage count as they fell to a rare home defeat which further dents their hopes of qualifying for the knockout rounds.

The sides meet again on 14 January at Thomond Park.

Line-ups

Northampton: Furbank; Ramm, Proctor, Hutchinson, Freeman; Smith, Mitchell; Waller, Matavesi, Painter, Salakaia-Loto, Ribbans, Scott-Young, Ludlam (capt), Augustus.

Replacements: Haywood, Iyogun, Petch, Moon, Hinkley, Braley, Dingwall, Skosan.

Munster: Haley; Nash, Frisch, Crowley, Earls; Carbery, Murray; Loughman, Scannell, Ryan; Kleyn, Beirne; O'Donoghue, O'Mahony (capt), Coombes.

Replacements: Barron, Kilcoyne, Salanoa, Hodnett, Kendellen, Casey, Scannell, Daly.

Match officials

Referee: Pierre-Baptiste Nuchy (France)

Touch judges: Jonathan Gasnier and Kevin Bralley (France)

TMO: Eric Briquet-Campin (France)