Frank de Boer felt he was "unlucky" during his ill-fated spell in charge of Crystal Palace.
The Dutchman lost his job after just four Premier League games earlier this season.
And De Boer believes the key to his downfall was an injury suffered by winger Wilfried Zaha.
"I was really unlucky that he got injured in the first game, I missed him for the next six games, he had a huge impact on Crystal Palace, because he can create something out of nothing, he can play for a much bigger club.
"He can move beyond Crystal Palace, that's for sure, I'm 100 percent convinced of that," said De Boer.
Asked whether a transfer during this window would be good for the attacker, De Boer replied: "Not really, because he has to play every a game every week, I think that's the most important thing for him."