Daley Blind joined Man Utd in 2014
Eric Bailly joined from Villarreal for £30million earlier this month but the Daily Star Sundayclaim Jose Mourinho still wants to strengthen his defence.
Chelsea have been strongly linked with Bonucci, who is currently managed by incoming boss Antonio Conte with Italy.
According to the Sunday People, Mourinho believes Blind is too small to play at centre-back.
And that has supposedly alerted Gunners boss Arsene Wenger to his potential availability.
Zlatan Ibrahimovic's agent Mino Raiola has insisted no decision has been made about the Swede's future but heaped praise on Manchester United, who are favourites for his signature.
“Manchester United are a great team, with a great Coach,” he told Telefoot.
“It’s fascinating. I’ve made my decision, but he hasn’t made his. He’s really busy with the Euros.
“Out of respect for the Euros, the team, the country and the Coach he has to be professionaland concentrate on that.”