It was the first time that Sandberg spoke publicly about his injury. Doctors had to remove a portion of his skull to relieve swelling so he is not yet back in school and is still undergoing physical therapy. Nevertheless, he had a lot to say about the baseball controversy over banning metal bats from high school baseball games.
Sandberg doesn't remember much from the day that line drive hit him in the head and left him in a three-week coma, but there is nothing about Sunday that he'll ever forget.
"Just to see all these guys that I've idolized and just to be out here it's great," said Sandberg.
At the Bay Bridge series, Sandberg got a pregame locker room visit, autographs on the helmet he now wears through his recovery, autographs on his jersey, and even a little face time with Giants pitcher Barry Zito.
So what more could a 16 year old pitcher ask for?
"To play baseball," said Sandberg.
It's the one thing Sandberg hasn't been able to do since he was injured on the mound two months ago during a game against De La Salle. And it was Zack Bryers who hit that line drive with an aluminum bat.
"It sounded like a slap to me. I thought it hit his glove at first, then when I glanced over and I saw him on the ground, I was in shock," said Bryers.
From opposing players to lifelong friends, on Sunday it was Bryers who was on the receiving end when Sandberg threw the ceremonial first pitch and Gunnar's entire Marin Catholic High team standing behind the mound.
They are now on a crusade to eliminate aluminum bats from their league and it's a debate that goes on inside and outside the Coliseum.
"Even at our age, I've seen some line drives that come off the bat pretty sharp off an aluminum bat," said George Williams, a little league coach.
A's relief pitcher Brad Ziegler spent six days in ICU, after taking a line drive to the head in the minor leagues.
"I definitely think aluminum bats are more dangerous, but at the same time that doesn't mean the dangers are not there with wood bats," said Ziegler.
"I think wood is just much safer and I mean if the pros use it, I don't see why we shouldn't," said Sandberg.
Sandberg has another surgery this coming Tuesday, but says he hopes to be back out with his team next school year.
As for which team Sandberg was rooting for on Sunday, underneath his A's jersey, he wore a Giants t-shirt.