Jones sat out the recent win over France, while Davies hasn't worn Welsh colours since the opening Dove Men Series Test against South Africa in early November, but their international experience and star quality means they will be back in the thick of the action at Twickenham.
Lancaster now faces a similar dilemma with Lions tourist Manu Tuilagi after the Samoan-born centre made his long-awaited comeback from a chest injury at the weekend. Tuilagi was one of his country's standout performers last season but he hadn't played since mid-September prior to featuring for 69 minutes for Leicester at Newcastle three days ago.
Tuilagi's game-breaking ability has led to suggestions of an immediate recall to the first XV but George North's Northampton team-mate Luther Burrell has shone in his absence and Lancaster looks set to stick rather than twist when he announces his team on Friday morning.
"I don't feel any pressure (to bring Tuilagi back), the only pressure I feel is to do what's right for the team," Lancaster, who also has London Irish wing and fellow injury victim Marland Yarde back in the selection mix, told the RFU website.
"You've got to be fair to the players who have played and played well but also recognise Manu's quality. You have to be fair to him and give him the chance to get some games under his belt, while also giving him time to get used to our systems and structures. We've moved on quite a lot since he was last in camp with us and it will be good to see him get up to speed with everything.
"We'll see how it goes but obviously it would be a big step, in particular for Manu as he has only played one game and he has not trained with us all year. Marland has been with us a bit longer and obviously we've got some decisions to make there. He played well at the weekend - he played the full 80 - but it's still quite a big step."
England have won six of their eight fixtures without Tuilagi - two when he was with the Lions in the summer and four since he was sidelined - and Lancaster believes his men are in a good place ahead of the clash with Wales.
Narrow defeats to France and New Zealand courtesy of late tries are the only blemishes on England's record since Wales beat them 30-3 in Cardiff last March and Lancaster has been delighted with the way they have responded to that record-breaking reverse at the Millennium Stadium.
"We've had a good winning record since that point: we went to Argentina and played well, then we had the QBE internationals and won two out of three when it probably could have been three out of three. We were disappointed to lose in France but we're in good shape overall," added Lancaster, who is expecting a red hot atmosphere at RFU HQ.
"And the team has changed quite a lot since that point, mainly through injuries, but that has created opportunities for other players in our squad, which has created more depth than we've had before.
"I'm pleased that the fans can see the direction that the team is going in and that they're behind the team. You can sense that in the atmosphere and in the engagement before the game when you're coming off the bus and then during and after the game. I think people in England recognise that it's a young team developing but it's a team that plays with its heart on its sleeve and also with a passion for being English."