Wenger surprised some Arsenal supporters when he stated earlier this month that he has no intention of signing another forward, even though his attacking line looked a little weak last season with Olivier Giroud and Yaya Sanogo as his lead marksmen.
Sanchez, who signed from Barcelona last month, has often been utilised as a winger throughout his career, but Wenger believes the Chile star can thrive in a more central role.
"He is a striker and he's a good finisher," Wenger told Arsenal's official website. "He made a great impression in Italy [with Udinese] -- I saw him there and he was really outstanding.
"Then at Barcelona it was a bit more difficult, but it's like you could see with Neymar at Barcelona, because there you have Lionel Messi. You see Neymar with Brazil and Neymar with Barcelona and it's not the same. I like the fact he can play left, right, up front and that's why I went for him.
PREMIER LEAGUE'S LONGEST SERVING BOSSES1) Arsene Wenger (Arsenal) -- hired Sep. 30, 1996
2) Alan Pardew (Newcastle United) -- Dec. 9, 2010
3) Sam Allardyce (West Ham United) -- June 1, 2011
4) Nigel Pearson (Leciester City) -- Nov. 15, 2011
5) Brendan Rodgers (Liverpool) -- June 1, 2012
6) Paul Lambert (Aston Villa) -- June 2, 2012
Wenger successfully converted Frenchman Thierry Henry into a potent leading striker after signing him as a winger.