Watch David Letterman Surprise Crowd with Donald Trump Top 10 List [VIDEO]

David Letterman made an unannounced stage appearance to deliver a fresh Top 10 list on Donald Trump's presidential bid.

A San Antonio crowd definitely got more than they bargained for when a now bearded David Letterman returned to the stage for the first time since retiring from the Late Show on May 20th. It happened during Steve Martin and Martin Short's A Very Stupid Conversation comedy show in San Antonio, Texas on Friday (July 10th).

The crowd roared as David Letterman entered, as he commented, "I retired and I had no regrets. None. I was happy."  He adds, “and then a couple of days ago, Donald Trump said he was running for president.  I have made the biggest mistake of my life, I tell you."  Laughter erupted on this reference to potentially missing all this new joke material.

On this night, he would get his chance to tell jokes with a signature Top 10 list.  Letterman reached to his jacket saying, "every suit I own comes with a Top Ten list," preparing to share his "interesting facts about Donald Trump."

Trump's hair was clearly the main target saying, "that thing on his head."  It all stared with, "number 10: that thing on his head was the gopher in Caddyshack."  Weaving through the list, finding a clever way to work in his friends, "number 2: Donald Trump has pissed off so many Mexicans that he's starring in a movie called No Amigos."  A homage to "Three Amigos" stars, Steve Martin and Martin Short.

Watch David Letterman's surprise Top 10 list below.