Glasgow are bottom of Pool Four with nothing to show for their efforts after defeats to Northampton and Ulster.
The Warriors now face a double header against Castres knowing that only victories will give them any hope of continuing interest in European competition.
After successive PRO12 defeats to Leinster and Munster Mike wants the Warriors to get back to winning ways when they face the French.
He said: "I am absolutely delighted to have signed the three-year deal and for me the best way to celebrate that would be to do everything I can to help Glasgow to a win on Friday night.
"Our pride has been hurt by what happened against Munster and we know we have a lot to make up for.
"We have to prove that last Saturday was a bad day at the office and this Heineken Cup tie with Castres is the perfect opportunity to prove that. Really, it is an all or nothing situation. If we get the win then we would be going to Castres having badly damaged them but also handed ourselves a life line.
"It would be a massive stepping stone and we know that we will have a big crowd out at Scotstoun on Friday night and that we owe them a win on home soil. We'll do everything to make sure we leave nothing in the locker.
"We know all about the reputation of the Castres pack, but we have held our own against Ulster and Northampton up front and we are determined to more than match Castres.
"For me this is exactly the type of game I came to Glasgow to play in and Friday night can't come quickly enough.
"Defeat is just not an option for us and this is a great chance to deliver the type of performance that will make the support proud to be Warriors fans."