Real official Miguel Portugal watched the Ecuadorian in action against Manchester United in midweek and is understood to have stayed on after the game to initiate talks with Wigan chief executive Brenda Spencer.
According to the Mirror, the Spanish giants have tabled an offer of £16 million, but with United their main competition in the race to secure Valencia's signature, Wigan's asking price is expected to be around £20m.
'It's inevitable Antonio will leave, but where he goes I'm not quite sure," he said. "There are no deals done at all. I keep reading that one, but nothings been done.
"I believe someone from Real Madrid is flying in and I've also heard Bayern Munich have been knocking on the door.
"Whether that is true, I don't know.
"At the end of the season I'll sit down and have a chat with Antonio. But I know it will be difficult to keep him."
For now however, United look to be maintaining the upper hand over their European rivals.
Firstly, Madrid will have to complete their presidential elections before any summer signings are permitted to go through, and secondly, Sir Alex Ferguson is prepared to offer Bruce a couple of young United payers on year-long loan contracts as part of any deal.
The former United defender is said to be keen on having Fraizer Campbell and/or Danny Welbeck.