Keown says Emery has taken Villa to a new level.
He wrote for the Daily Mail: "Unai Emery is taking Aston Villa to new-found heights. They are still in the hunt for the Champions League top five places, fighting to become European champions and two games away from lifting the FA Cup.
"Even the great Villa sides of the 1980s that won league titles and European Cups were never so deep in so many glittering competitions in the same season as they are right now. This could be their most successful ever season.
"Emery has carefully rebuilt Villa with real vision and has now created an expectation for success. He’s given Villa the perfect platform to journey through a minefield of difficult fixtures that will ultimately define their season and their history.
"A week that started in the FA Cup against Preston and a very impressive victory against Brighton now takes them up against high-flying Nottingham Forest before a Champions League double header against Paris Saint-Germain and an FA Cup semi-final against Crystal Palace also on the horizon.
"Emery has been decisive in the transfer market, both in the summer and in January. The experience he has brought into the dressing room in the form of Marcus Rashford and Marco Asensio, both on the scoresheet against Brighton, have both been crucial."