The Wales international has been regularly linked with a move to Manchester United since Bale came off the bench to score twice in the Champions League final.
Bale put himself in the shop window with an impressive brace to help Real Madrid ease to a 3-1 win against Premier League side Liverpool FC in Kiev back in May.
The 28-year-old has been touted as potential target for Manchester United since Portuguese head coach Jose Mourinho took over the reins back in 2016.
Bale has won four Champions League titles, the La Liga crown and the Copa de Rey since his move to Real Madrid from Tottenham Hotspur in £85.3m deal in the 2013 summer transfer window.
Sunday Times reporter Castles believes Manchester United have a strong chance of signing Bale in a big-money deal in the current transfer market.
“Bale is a strong possibility because of the situation at Madrid. They have to wait and see what Bale’s ultimate decision will be,” Castles told the Transfer Window podcast.
Manchester United finished in second place in the Premier League table last term to secure their best finish since Sir Alex Ferguson’s retirement in 2013.
The Red Devils lost 1-0 to Chelsea FC in the FA Cup final at Wembley back in May following Eden Hazard’s winner.
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