Football

I don't understand what this means...

On Sports Illustrated's website, there's a photo gallery featuring SI's list of the "10 Most Feared NFL Players." Number one on this list is Pittsburgh Steelers linebacker Joey Porter. Alongside Porter's photo is a caption stating that Patriots quarterback Tom Brady "nearly started shaking" the first time he saw Porter across the line.

What does it mean to nearly start shaking? To me, this simply means he didn't shake -- then went on to win three Super Bowls in four years.