Grealish could return to his boyhood club for the first time tonight, but spoke about how he nearly turned out for the red side of Manchester in a fascinating interview with the Daily Telegraph.
"I was really close to going, but nothing happened in the end," he said.
"We played United in a pre-season game on Saturday and I wasn't supposed to play in a cup game at Burton.
"But after the United game I said to Christian Purslow [Aston Villa's chief executive] and my agent 'if I'm not leaving, I'll sign my new contract'.
"I went in with my dog on Tuesday morning, signed the deal, and played later that day. We all agreed on the clause and if any team hit that, it's a win-win because it means I've had an unbelievable season and Villa got £100 million."
The 26-year-old has scored two goals and registered three assists in 15 appearances since making the switch to the Etihad Stadium.
Grealish is unlikely to start tonight's match at Villa Park, but may make an appearance from the bench against his former team.
City are currently sandwiched in between both clubs in second place with 29 points from 13 games - one behind league leaders Chelsea and one ahead of third-place Liverpool.
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