Scarlets head coach Simon Easterby labelled his side's showing against Leinster as being "terrible" after they fell to a heavy 42-19 defeat on Friday.
The Welshmen were 13-0 ahead in the early stages at Parc y Scarlets but then suffered a dismal rest of the game in their PRO12 opener.
"We've got a point to prove after this game never mind last season," Easterby told BBC Sport when looking ahead to their next fixture, against Treviso.
"We were terrible [against Leinster].
"We've got a lot of work to do starting now to make sure we don't embarrass ourselves like that.
"But we're not going to over-react just one game into a very long season.
"We also know what promise and ability we have in this side and when we've shaken off the disappointment, there was plenty in the game for us to build from.
"This is a time for strong and clear leadership from our senior players and the coaches."