Munster set up an all-Ireland Celtic League semi-final against Ulster at Lansdowne Road next week when they shrugged off the stiff challenge of Llanelli at Thomond's Park, Limerick.

An opportunistic second-half try from scrum-half Mike Prendergast, standing in for late injury withdrawal Peter Stringer, was ultimately the difference between the two sides in a tight encounter watched by new Ireland coach Eddie O'Sullivan.

But Munster, still reeling from the news that coach Declan Kidney is to leave them at the end of their Heineken Cup campaign to join O'Sullivan as Ireland's assistant coach, continued their unbeaten run at their Limerick stronghold.

Llanelli had the lion's share of first-half possession but failed to translate that dominance onto the scoreboard.

It was a tetchy opening period with Munster prop Peter Clohessy and his Welsh counterpart John Davies participating in a running battle throughout.

Indiscipline

Both were warned as early as the 11th minute by Scottish referee Rob Dickson as Munster conceded a penalty and Scarlets' captain Stephen Jones sent over the kick to open the scoring.

But it was an indiscretion by Davies which led to Munster levelling the scores in the 23rd minute.

The prop was penalised for deliberately killing the ball as Munster drove for the line.

The Irishmen were denied a try scoring opportunity however when referee Dickson blew his whistle rather than playing the advantage.

Davies was sin-binned and Ronan O'Gara sent over an easy kick which ended the first half scoring at 3-3, the Irish fly-half missing a 25th minute penalty.

Scoring opportunities were rare but O'Gara made no mistake when his next chance came, seven minutes into the second half, and he put Munster 6-3 in front.

In fact in was not until the hour mark that the game really opened up.

Llanelli got their scrum put in badly wrong on their own 22 and, as the ball shot out the back, Munster's Prendergast stole a march on opposing scrum-half Guy Easterby to pick the ball up one-handed and run over for a vital try.

O'Gara sent over the conversion and finally, at 13-3, there was breathing space between the two sides.

Jones responded with a penalty for the Scarlets that reduced the deficit to just seven points but Llanelli failed to mount the sort of pressure that would bring them that vital try and conversion.

Munster: Try: M Prendergast. Con: R O'Gara. Pens: O'Gara 2.

Llanelli: Pens: S Jones 2.

Munster: Staunton; R Henderson, J Kelly, J Holland, A Horgan; R O'Gara, M Prendergast; P Clohessy, F Sheahan, J Hayes, M Galwey (capt), M O'Driscoll, A Foley, A Quinlan, J Williams,
Reps: D Crotty, K Keane, J Blayney, M Horan, D O'Callaghan, P O'Connell, D Hegarty, M Mullins.

Llanelli: B Davies; W Proctor, M Cardey, S Jones, G Evans; G Bowen, G Easterby; M Madden, M Thomas, J Davies, V Cooper, C Gillies, C Wyatt, I Boobyer, S Easterby.
Reps: P Booth, R McBryde, S Morgan, D Jones, D Peel, N Boobyer, S Finau.

Referee: Rob Dickson (Scotland).