Consider the question. Michael Buffer (born November 2, 1944) is an American ring announcer for boxing and professional wrestling matches. He is known for his trademarked catchphrase, "Let's get ready to rumble!", and for pioneering a distinct announcing style in which he rolls certain letters and adds other inflections to a fighter's name. His half-brother is UFC announcer Bruce Buffer.

Who trademarked let's get ready to rumble?
If the answer is 'Michael Buffer'; explain the reasoning:
To answer this question, we should know that: He is known for his trademarked catchphrase, "Let's get ready to rumble!", and for pioneering a distinct announcing style in which he rolls certain letters and adds other inflections to a fighter's name.