Chile international Sanchez swapped the Gunners for Manchester United in January 2018.
"It's a strange one when you talk about Alexis Sanchez because, when you look back at his Arsenal days, you're talking about one of the Premier League's best attackers," Ince told Paddy Power. "He was a great player there.
"As a pair, they just had this telepathy with each other, they instinctively understood each other, they knew the runs the other were going to make without looking.
"Most good things that Alexis did at Arsenal were connected with Ozil.
"And it works both ways, they made each other better – look at Ozil since Sanchez left, he's not been the same player. Neither have."