The Finland international midfielder is recovering from an operation carried out after Leeds’ win at Leicester City, but manager Simon Grayson is hopeful of seeing him recover in time for next weekend’s Yorkshire derby against Barnsley.
Grayson said: “He’ll be out of this weekend, but he might be back for the following weekend.
“With hernia operations these days players don’t take too long to recover, but we don’t want to be rushing him back too quickly.”
Vayrynen has featured regularly in Grayson’s match-day squads since joining on a free transfer in September, and United do not expect his operation to lead to an extended absence.
Robert Snodgrass, meanwhile, is fit to play at Turf Moor despite Grayson revealing that the winger required surgery on a thumb injury suffered during Leeds’ win at Leicester.
The minor procedure forced Snodgrass to withdraw from Scotland’s recent friendly in Cyprus but he has been passed fit by United’s medical staff after having a cast removed.
Grayson said: “He had an operation straight after the Leicester game, but he’s trained all week and he’s fine. It just meant that he couldn’t be available for Scotland because he was wearing a cast.”
Darren O’Dea, Andy Keogh, Aidan White and Mikael Forssell have all emerged unscathed from international duty and are in contention for United’s BBC-televised trip to Turf Moor.