Milan face a tricky tie to reach the Champions League group phase.
"We are working well and the team is getting stronger every day," Boateng told topmercato.com .
"There are still almost two weeks before we have to take it seriously, so we are perfectly within the planned schedule.
"Even if our results in pre-season weren't exceptional, I think the side did pretty well. We only had a few problems against Manchester City in the Audi Cup, when we conceded five goals in the opening half-hour, but I can assure you we will be ready for the Champions League play-off."
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