If you're prone to being speechless at times of high pressure, this definitely isn't the job for you. People want to hear you speak, and if you're too overworked or nervous to open your mouth, you're not going to be able to get the job done.
That's just one of several stressful factors pressing down on your dreams of calling big games. There are pressing deadlines, difficult-to-handle athlete egos, and producers breathing down your neck any time you slip up verbally, misquote someone, or say something even potentially offensive.
If you're the type who thrives in high-pressure situations and loves hauling tail to make deadlines with zero flexibility, then you're in the right place.
You also shouldn't be the kind of person who worries about how badly your wrinkles show up on film. That's for the make-up person to worry about.