Leeds were closing in on Aarons after agreeing a deal with Norwich City, for a fee which could reach £12m, and many felt the capture of the highly rated full-back would be a big coup for the Whites.
They will not be signing Aarons though, with the defender sensationally walking out on a medical with the Whites.
Leeds were putting Aarons through his medical paces when Bournemouth made their move.
The lure of playing in the Premier League was too strong for Aarons to resist and he is expected to complete a switch to Bournemouth within the next 24 hours.
The development leaves Leeds licking their wounds and it is unclear who the Whites will turn to next.
Leeds are set to boost their defence though by landing Joe Rodon.
A loan deal, running for the season, has been agreed with Spurs for the centre-back, who is Elland Road bound.
