"He is one hell of a player and a great team guy, a big name who has come out here with a humble attitude and a great work ethic," Muir told the Argus.
"We did not realise what a coup it was signing him from a publicity perspective as we've had several TV crews out from Europe following him around Durban."
Muir said the Sharks were looking for Michalak to display his French flair.
"We're not looking for anything typically South African from him," he added.
"He is different and we've always said he has got something special. So we are confident that he will be pretty successful and up there with some of the best signings we've had."
Michalak's start means Springbok Francois Steyn moves to full-back at the expense of Stefan Terblanche in the Sharks side named for the match.
Sharks team: Francois Steyn, Odwa Ndungane, Waylon Murray, Bradley Barritt, JP Pietersen, Frederic Michalak, Ruan Pienaar, Tendai Mtawarira, Bismarck du Plessis, BJ Botha, Johan Ackermann, Johann Muller (capt), Jacques Botes, AJ Venter, Ryan Kankowski.
Reserves: Craig Burden, Jannie du Plessis, Albert van den Berg, Keegan Daniel, Rory Kockott, Adrian Jacobs, Stefan Terblanche.