Aberdeen remain keen to sign Scotland international Shaun Maloney – even if the 34-year-old would be unable to feature in the Europa League qualifying campaign.
The former Celtic player was expected to sign for the Dons on Monday but the move has been put on hold due to an injury concern.
The Dons are keeping quiet on the nature of the injury that has delayed the signing but it is understood Maloney requires a hernia operation after putting surgery on hold to try to help Hull City avoid relegation from the English Premier League.
If that is the case, Maloney would be sidelined for four to six weeks and would miss the upcoming Europa League qualifier against either NK Siroki Brijeg from Bosnia or Kazakhstan side Ordabasy.
It is a major blow for the Dons who have also been dealt a setback in their hopes of signing Preston forward Stevie May.
Preston are expected to name Alex Neil, the former Norwich City and Hamilton Accies manager, as Simon Grayson’s replacement following his move to Sunderland.
May is expected to be part of the Preston squad that takes on Bamber Bridge in a friendly on Friday before heading to a six-day training camp in Ireland and unlikely to be granted a move back to Scotland until the new Deepdale manager has assessed his squad.
Aberdeen manager Derek McInnes, meanwhile, has stepped up his hunt for a new central defender to replace Ash Taylor – and could be poised to bring a former Don back to Pittodrie.
McInnes is interested in 34-year-old Icelandic international Kari Arnason, who spent last season in Cyprus with Omonia.
Arnason joined the Dons in June 2011 and scored three goals in 40 appearances for the Dons.
The central defender moved to Rotherham United the following summer and spent three years with the Millers before joining Swedish side Malmo in 2015.
Arnason moved to Cypriot side Omonia in January but the player is currently a free agent and looking for a new club.