Scottish champions Celtic have reportedly had a bid of around £3.5m knocked back by rivals Aberdeen for centre-back Scott McKenna.
The Hoops are said to have made their move on Tuesday, despite the Dons' insistence that the defender will not be sold during this transfer window.
Celtic are on the lookout for cover at the back as Dedryck Boyata's future is uncertain, having pushed for a move to Fulham earlier this month.
BBC Sport suggests that Brendan Rodgers's men have been unsuccessful in their attempt to snap up McKenna, though, with Aberdeen also knocking back previous offers from Hull City and Swansea City.
McKenna has been capped four times by Scotland at senior international level since making his debut in March.