Tuchel did impressively well to lead the Blues into a top four finish as well as land the Champions League trophy in his first four months in charge.
"All the signs are there that they're definitely looking for a striker," the former Blues winger told SBK Sportsbook. "They may buy a defender or two, but other than that there's [not] much more you can do with that brilliant Chelsea team.
"It's actually growing in depth and quality, so it's a very strong squad and there is money to spend as there always is.
"They were great at scrappy 1-0 wins - but if you've got Jorginho as your top goal scorer on seven goals and they're all penalties, I see that as the problem for any team challenging for the Premier League title against the attacking might of Manchester City."