The Manchester United striker is close to joining Inter.
And former teammate Di Natale told La Gazzetta dello Sport: "Sanchez to Inter would be an extraordinary coup and a gamble that both parties could win comfortably.
“Alexis is an exemplary professional, someone who always arrived early for training sessions and never held back during a match. He is returning to Italy, where he left an excellent reputation, and he was strongly wanted by a great coach like (Antonio) Conte, who had asked for his signature back when he was at Juventus.
“He has all the ingredients needed for a great season. Alexis needs people to have faith in him and I am sure he'll do well with Conte. I think he had some fitness problems over the last 18 months and he certainly had difficulty settling in at Manchester United.
“Sanchez has to play consistently and feel important to give his best. That didn't happen in Manchester, but it's impossible to doubt his talent.
“He'd also be playing the 3-5-2 system with Conte, which he had at Udinese under Francesco Guidolin and allowed him to become a decisive player. He'll have Romelu Lukaku by his side and as a second striker, Alexis becomes impossible to mark with his pace and power.
“You'll see, he will score many goals," continued Di Natale. “His time in England seemed to be over, as he needed a new challenge and Inter are the right club for a relaunch, with Conte the best Coach to get him back to the top level.
“I can assure you, Sanchez will want to prove himself in Serie A."