Victory for Munster puts them in the driving seat with three rounds of action completed but Welch and the squad are looking forward to the challenge in Limerick.
"It should be a great occasion and I have never played at Thomond Park before," said Welch.
"Everyone is looking forward to it because we know where we slipped up on the weekend and we know what we need to work on.
"We all play rugby to play in these games.
"When you ask a player why he does what he does it is to play in the big occasions against the big teams and the big players.
"It is a real honour, and you want to keep playing them."
Having previously only made one start in the Heineken Cup, Welch has started all three of Scarlets' games to date and he is enjoying having a starting berth in the side.
"I have enjoyed it this season because I have managed to bed myself in a bit more," he added.
"This is the longest run I have had during my time here with 12 back to back games including one on the bench.
"It is a case of taking opportunities when they come otherwise there are others who will take your place.
"It has been good to get a run of games and good to play in these big European games as well.
"You feel a lot more sure of yourself in the side which is a great thing."