The Ukraine international has taken his chance at left-back this season - and impressed.
Guardiola admits Zinchenko belongs further forward, but says: "If Zinchenko has to defend for 90 minutes, he is going to suffer.
"But if we dominate the game he can help us a lot.
"In many cases we have seen players like wingers play as full-backs or midfielders playing as centre-backs.
"I think players that play further forward can play in defence - they can adapt to the position - but for example a centre-back playing in midfield might be difficult."