The Kumasi giants are without a head coach following the sacking of Zdravko Lugurasic in April, due to a poor run of results.
Despite the sacking of the Croatian manager, Kotoko have gone seven games without a win under Godwin Ablordey and Frimpong Manso, including a 2-0 defeat against Great Olympics last weekend.
Polack insists he is ready for the task ahead, noting that he can't control the egos of the players.
"I've signed for Asante Kotoko until the end of the season but I have an option to extend one additional year," Polack told Goal.
"I'm ready for the challenge and have begun work today. I will meet the backroom staff so they will know what I expect from them in the coming months. I know that there are players with good prospect and hype but I don't care if you're Messi or Ronaldo, you'll have to prove to me why you must play in every game," he said.
He added: "I don't think Berekum Chelsea striker Stephen Sarfo will join me here but Sadick Adams will arrive in Ghana to join Kotoko. I know he will help my course just like every player at the club but the supporters must lower their expectations since I'm not a magician."
Polack becomes the fourth coach Kotoko have appointed this season but he is unlikely to be in the dugout when Kotoko welcome Tema Youth to the Baba Yara Sports Stadium on Sunday in the final game of the first round of the season.