Unai Emery expects Arsenal supporters to give Jack Wilshere a warm welcome when he returns to Emirates Stadium as a West Ham player, while opposite number Manuel Pellegrini questioned why the midfielder was allowed to leave North London.
Wilshere is set to line up against Arsenal for the first time when the Hammers visit the Gunners in search of their first points of the season on Saturday and Emery said the 26-year-old remains a well-respected figure around the club.
The midfielder made 125 Premier League appearances in 11 years as an Arsenal player, before he was allowed to leave on a free transfer in July.
Emery expressed his admiration for Wilshere and said the move was made in the best interests of his career, telling reporters: "I spoke with him for 15 minutes here in Colney before he left.
"The first thing for me is I have respect for his career here. And then, he chooses what the best was for him in his future.
"It's for that, on Saturday, I know that here the supporters like him and have this respect also. I think there is a good reception for him here.
"Then we are going to play and we are going to think after that, for us to win. But, I [hope] the best for his career."
Wilshere played the duration of West Ham's opening two matches of the season against Liverpool and Bournemouth, both of which ended in defeat for Pellegrini's men, and he is expected to start against Arsenal.
Pellegrini spoke of the occasions his Villarreal and Manchester City teams faced Wilshere and praised the playmaker's performances.
"I played here three years against Arsenal, and before that with Villarreal in the Champions League," said Pellegrini.
"Jack was always a very good player. I don't know the reason why he finished his contract with Arsenal.
"I don't know why Arsenal allowed him to come here."
