Full-back Davies picked up a knee injury in the 20-16 defeat to the Blues on Wednesday while Thomas is out of the reckoning with back trouble. The match at the Racecourse Ground in Wrexham will be the Scarlets' third outing in eight days but director of rugby Gareth Jenkins believes his squad will be able to cope.
"We've been able to balance our selection so hopefully we won't be affected too much by the injuries," he said. "We've taken a few casualties and that might pressurise our selection, but we knew this was in front of us and we were quite clear about what this week meant."
Connacht beat the Blues at home in their first game of the season, but will arrive in North Wales on the back of a 34-3 defeat to Edinburgh Gunners.
"They'll be resilient and tough, and will make life really awkward for us," added Jenkins. "They will probably be fresh and they are always capable of tripping sides up."
GB7s women left their England base to train in Wales this week. Olympic Games hopeful Rachael Burford gives WRU TV's Graeme Gillespie her thoughts on Welsh teammate Jasmine Joyce - a 'one touch wonder'
The GB7s women's squad is currently training at Wales' Centre of Excellence where assistant coach Richie Pugh tells WRU TV's Graeme Gillespie some 'tough calls' will have to be made when it comes to finalising the 12 spots for Rio's Olympic Games.
Wales U20's Billy McBryde is looking forward to starting his first game against New Zealand this afternoon in the World Rugby U20 Championship where his side are looking to gain revenge from last week's pool defeat to the Kiwis.