It is a second defeat on the bounce for Pivac's troops after losing at Glasgow Warriors in the GUINNESS PRO12 last time out.
Scarlets currently sit eighth in the PRO12 and don't return to action in the competition until mid February when they clash with Pat Lam's Connacht.
Two tries from Harry Robinson and one for Rob Evans, as well as two Rhys Priestland penalties, were not enough to keep up with the clinical Tigers.
However Pivac insists the spirit the side showed will serve them well going forward.
"The boys wanted to move the ball around. I thought the first half in particular, when we had possession, we made good in-roads. We got a good try and it was game on at half time," he said.
"In terms of the 80 minute performance we're obviously disappointed with their tries from set piece but I thought the boys played well.
"The sorts of players that are missing do make a difference, you're talking about a lot of international players in certain positions.
"The team we had out there was what we had to work with and over the 80 minutes, generally speaking, they put up a pretty brave effort."
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