The Udinese striker, who partnered Sanchez for three years in Serie A, says he could do with working on the heading side of his game.
He told Arsenal's official website: "Alexis is able to do everything, he's one of the most complete attackers in the world: he could play as a winger, as a striker, as an inside forward.
"At Udinese, there were even emergencies where he filled in as a midfielder! But that's not to say he can't get better.
"When a player thinks he has no need to improve, he's close to the end, he's destined to be dethroned. Sanchez, on the contrary, has always shown a hunger to get better, and he's always been willing to sacrifice the sweat and tears to do so.
GETTY
Antonio Di Natalie believes Alexis Sanchez has room for improvement in the air
Like me, he's not a giant: maybe there is scope for him to become a better header
Antonio Di Natale
"I never got the sense that he was satisfied with what he achieved.
"This lack of complacency has helped him to become the star he is, and it is what will help him remain on the top for many years.
"It's hard to say exactly where he can improve. Like me, he's not a giant: maybe there is scope for him to become a better header of the ball. Maybe..."
And the Chilean would do well to heed the Italian's advice, who is currently the seventh highest scorer in Serie A history.
Invalid email
We use your sign-up to provide content in ways you've consented to and to improve our understanding of you. This may include adverts from us and 3rd parties based on our understanding. You can unsubscribe at any time. Read our Privacy Policy
