Munster picked up a bonus-point win against Scarlets as the United Rugby Championship returned from the international break.

But scores from Jack O'Sullivan, Thomas Ahern, Sean O'Brien and Shay McCarthy ensured Munster returned home with maximum points and up to sixth place.

Scarlets remain 14th with just two wins all season.

Head coach Dwayne Peel had hoped the month's break and return of injured players would ignite a revival, but Munster too travelled to Llanelli with ambitions of climbing up the URC table.

In perfect playing conditions, both sides turned down kickable penalties in the early stages and for Munster it paid off.

They won a penalty off line-out ball, opted for a quick-tap and there was no stopping the power of number eight Coombes from a metre out.

It was mostly one-way traffic in the first half after that, Munster spending large periods camped on Scarlets' tryline.

Despite some brave defending, none more so than Archie Hughes' try-saving tackle on prop Jeremy Loughman, Coombes eventually burrowed over for his second.

The returning Johnny McNicholl looked lively when Scarlets did have possession, his evasive running causing Munster all sorts of problems, but Scarlets' discipline and inaccuracy were left wanting.

Munster could have got a third just before half time, an interception saw double World Cup-winner RG Snyman hurtling towards the line, but Scarlets scrambled to chop down the powerful South African.

It was a similar story after the break, but Scarlets hit back against the run of play.

It all came from a moment of individual brilliance from Roberts who, like Kemsley Mathias, had been released from Wales' Six Nations squad to get some game time.

Roberts cut an inside line before racing into the Munster 22, and despite two defenders he somehow managed to carve his way through, get back to his feet to ground the ball.

It was the moment of inspiration Scarlets had desperately needed.

But it was Munster who continued to build, a looping long pass looked certain to put Mike Haley over on the wing, but Ioan Nicholas did well to bundle the full-back into touch.

Connor Murray, who had been released from Ireland's squad, looked to have crossed shortly after, only for his effort to be disallowed for obstruction in the build-up.

Replacement O'Sullivan eventually got the third try as Munster took complete control, while Ahern was over for the bonus-point shortly after.

O'Brien and McCarthy crossed on either wing to take the score past 40, as Scarlets fans once against headed for an early exit.

Scarlets: Johnny McNicholl; Tomi Lewis, Joe Roberts, Eddie James, Ioan Nicholas; Dan Jones, Archie Hughes; Kemsley Mathias, Eduan Swart, Harri O'Connor, Alex Craig, Sam Lousi (capt), Jarrod Taylor, Dan Davis, Vaea Fifita.

Replacements: Harry Thomas, Wyn Jones, Sam Wainwright, Jac Price, Teddy Leatherbarrow, Efan Jones, Charlie Titcombe, Steff Evans.

Munster: Mike Haley; Seán O'Brien, Antoine Frisch, Alex Nankivell; Shane Daly; Joey Carbery, Conor Murray; Jeremy Loughman, Niall Scannell, Oli Jager, Tom Ahern, RG Snyman, Ruadhán Quinn, Alex Kendellen (capt), Gavin Coombes.

Replacements: Eoghan Clarke, Josh Wycherley, John Ryan, Fineen Wycherley, Jack O'Sullivan, Ethan Coughlan, Rory Scannell, Shay McCarthy.

Referee: Ian Kenny (SRU)

Assistant referees: Adam Jones & Tom Spurrier (WRU)

TMO: Mike Adamson (SRU)