Tevez has told the club of his desire to leave so he can be nearer to his young daughters, who live in his homeland.
City thought they had reached an agreement to sell the striker to Brazilian club Corinthians earlier this week, but the deal fell through and the 27-year-old's future remains uncertain.
And England winger Johnson told Sky Sports News: "I hope he is (with the club this season) as he was our talisman last season scoring all his goals.
"A number of times he carried us in games with his goals and individual brilliance.
"Obviously he has his own reasons for what he is doing at the minute but he is a world class player and whatever he does I wish him all the best."
Roberto Mancini's side have been linked with a move for Tevez's compatriot Sergio Aguero and Johnson believes acquiring the Atletico Madrid man would be a great move for the Blues.
"He is world class," he said. "It would be great if he came and added to the squad we have. I watched him in La Liga over the last two seasons and he is an outstanding player."
Source: Team Talk
Source: Team Talk