Wasps boss Dai Young has played down any injury concerns surrounding England forwards Joe Launchbury and Brad Shields.
Flanker Shields did not start Wasps’ Heineken Champions Cup clash with Leinster on Sunday due to a side strain.
And Launchbury lasted just nine minutes of the 37-19 defeat in front of watching England head coach Eddie Jones at the Ricoh Arena.
Saracens, meanwhile, said on Saturday that their fly-half and England captain Owen Farrell had undergone thumb surgery.
Farrell has had a procedure to repair ligament damage and is expected to return to action in seven to 10 days, a time frame that would enable him to play against opening Six Nations opponents Ireland in Dublin on February 2.
Reflecting on Launchbury’s early exit, Young said: “Basically, he got his head in the wrong position in a tackle and his head hit one of the Leinster player’s hips.
“He went off for an HIA (head injury assessment), passed the HIA, but his neck really stiffened up. That is why he didn’t come back on, he was pretty stiff.
“He is OK in there (the changing room). We don’t see it potentially being an issue moving forward.
“He has passed his HIA, so that is not a problem, it is just a bit of a sore, stiff neck.
“He has had quite a few neck issues in the past, but we don’t feel this is anything serious.
“We are not going to chuck him out there if he is sore, but he is in the dressing room talking, but he is not hugely restricted.
“I would be very surprised if in the next 48 hours he is still struggling.”
And on Shields, Young added: “Yesterday after the team run he was doing a few extras and took a knock to his hip and the muscle went into spasm.
“He got a bit of a strain and was a bit sore this morning.
“He is going to be sore for 24 or 48 hours, but we don’t see them being a concern for England moving forward.”
Jones, meanwhile, must decide whether to call up injury cover for Farrell.
With England departing for their pre-tournament training camp in Portugal on Wednesday, his ability to take part in training could be severely restricted, throwing Jones’ preparations into turmoil.
The worst-case scenario would mean he is unable to take part in sessions until four days before the Aviva Stadium showdown.
Speaking after Saracens’ Champions Cup victory over Glasgow on Saturday, Saracens rugby director Mark McCall said: “Owen has been complaining – but not very much – about his hand being a bit sore.
“It turned out to be a very minor problem with a tendon in his thumb.
“As far as I know, he’ll be back in seven days, something like that, so he should be able to play a full part in the Six Nations.”