The Red Devils have been heavily linked with a move to sign the Sweden international in recent weeks after Ibrahimovic confirmed his intention to leave Ligue 1 champions Paris Saint-Germain at the end of the season.
Ibrahimovic scored twice on his final appearance for the French side to finish his spell in Paris on a high after four successive Ligue 1 titles, two Coupe de France and three Coupe de la Ligue.
Former United midfielder Keane has been previously critical of the lack of leaders in Louis van Gaal’s Red Devils squad as the 20-time English champions finished in fifth place in the table.
The ex-Republic of Ireland and United captain endorsed his former club’s pursuit of the towering Sweden international.
“I think he would be a good signing on a one-year deal,” Keane told ITV.
“He is a big player, a big character. I have said that United have been lacking a few characters and he would be a good fit there.”
United haven’t won the Premier League title since 2013 when Sir Alex Ferguson secured his final top-flight title.
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