On fields all around Northern California, high school baseball players will compete in the first round of the North Coast Section playoffs. But in several games, the equipment will be dramatically different: one team will be using metal bats and the other will be using wooden bats.
And 100 miles east in Sacramento, the state assembly will prepare to vote on a bill requiring that all teams switch to wooden bats.
Sandberg is inadvertently in the center of a debate about changing the rules of high school baseball in the name of safety. While his family hunkered down at Gunnar's bedside for much of the spring, the impact of his horrifying accident spooled out around them.
"We've been out of the loop on most of this -- we've spent two months taking care of Gunnar," said his father, Bjorn. "I just want to keep it from happening again."
On March 11, Sandberg, a junior at Marin Catholic High in Marin County, Calif., was pitching in a practice game. Normally a middle infielder, he was facing a player named Zac Byers, who was -- like almost all high school players -- swinging a metal bat. Byers hit a line drive that slammed into Gunnar's temple at about 100 miles an hour.
Sandberg was rushed to a hospital. His brain began to swell and he underwent emergency surgery to remove a portion of his skull, and was placed in a drug-induced coma.
"It got as bad as it could get," said Bjorn.
The community rallied around the family with fundraisers and action. The Marin County Athletic League, in a vote of solidarity, banned metal bats. Many believe metal bats cause the ball to leave the bat at a higher speed and are more dangerous than wooden bats. MCAL teams have played out the season using wooden bats, which some studies show to be safer.
Sandberg's recovery has been remarkable. After weeks in a coma and a stay in a rehabilitation hospital, he is now back home. On Sunday, he threw out the first pitch in Oakland at the A's-Giants interleague game. He was wearing a protective helmet -- something he won't have to wear after Tuesday's surgery to reattach a portion of his skull that was removed to allow his brain to swell.
His catcher behind the plate was Byers. The two have stayed in touch through Facebook, though Sunday was the first time they had officially met. The aftermath of the injury was shattering for Byers, a junior at De La Salle High.
"This is the best feeling I could have with this situation," said Byers, who said he received tremendous support from both his community and Marin Catholic's. "I'm so happy for Gunnar."
But the real happy ending would come if such accidents were preventable.
"Let's see what we can do to make it safer," said Bjorn Sandberg, who has heard from several families around the country, some whose stories end tragically. "Let's err on the side of safety."
California state assemblyman Jared Huffman authored a bill placing a moratorium on metal bats in order to allow schools to review and update safety standards. Metal bats are banned in North Dakota and New York City.
"It's time to seriously consider the safety of allowing kids to use performance-enhancing metal bats with the pitcher standing just 60 feet away with virtually no protection," Huffman said in a press release.
The Sporting Good Manufacturers Association defends the use of metal bats and has studies showing that a ball leaving a metal bat is no more dangerous than a wooden bat. Measures have been taken in recent years to minimize the Ball Speed Exit Ratio.
While there is also discussion about helmets and placing protective skull guards under caps, most of the focus has been on bats. Metal bats gained widespread usage in youth baseball, considered to be more cost-effective. But a high-end metal bat can cost as much as $400 these days, so some debate the savings benefit. Few debate that hitters generally have better averages swinging metal rather than wood.
A's pitcher Brad Ziegler, who met Gunnar on Sunday, was injured in Class A ball in a wood bat accident. Fred Lewis, now with the Toronto Blue Jays, hit a ball that hit Ziegler in the temple. Ziegler spent six nights in intensive care. Despite that injury, he has strong opinions about aluminum bats.
"I definitely think aluminum bats are more dangerous," he said. "They have more whip in them. You can see the bat bending. But that doesn't mean wood bats aren't dangerous.
"Some risk comes with the territory."
Taking measures to decrease the risk isn't as easy as it sounds. When asked to vote on wood vs. metal, the North Coast Section board soundly rejected the ban on metal bats, citing competition equity as the primary reason. In the playoffs, which begin Tuesday, that mindset has prevailed.
"We feel that our team would be placed at a competitive disadvantage by using bats different than what we have used all season," one athletic director said.
But the teams from Marin County are holding firm, even if they might be at a competitive disadvantage.
While Gunnar Sandberg has surgery to become whole again, his Marin Catholic teammates will take the field in Middletown, 75 miles north. They will think of Gunnar. And they'll be swinging wooden bats.