Newcastle United broke their record transfer fee to bring in Miguel Almiron from Atlanta United.
Ashley has made no secret of his desire to sell Newcastle, but no potential investor has been prepared to meet his asking price so far.
With Newcastle far from certain to stay in the Premier League, spending big money on the Tyneside club would have been a risk for anybody looking to buy.
However, with Almiron involved, Newcastle’s chances of staying in the top flight look strong.
And Allardyce believes that Ashley may have believed that Almiron was a good investment, as it could help Newcastle become a more attractive club to buy.
He said: “I think maybe we’ve seen Mike saying openly he wants to sell the club.
“Buying these players for Rafa saves Newcastle in the Premier League and finally someone might come along and give him the money he needs to sell the club. Everybody wins.”
Newcastle paid £20 million for Almiron, according to BBC Sport, which breaks a long-standing club record transfer fee.
The Magpies also brought in Antonio Barreca on what was a productive deadline day for them.
Newcastle are next in action tomorrow, when they take on Tottenham Hotspur at Wembley.
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