Lincecum, the team's two-time Cy Young award winner, issued a statement saying the attack on paramedic and father of two Bryan Stow, 42, after the March 31 Giants-Los Angeles Dodgers season opener was "senseless."
"This was a senseless act of violence, and I wanted to help out Mr. Stow and his family," Lincecum said. "It's also close to me because not only is Mr. Stow a Giants fan, but I have family and friends who are firefighters, police officers and paramedics and this honors their service to the community.
"I encourage Giants' fans to support Mr. Stow in a positive way and hope there are not any more unfortunate acts between fans in this great rivalry."
Los Angeles Police say they are seeking two men in connection with the attack on Stow, of Santa Clara, Calif., in the stadium's parking lot. At least $100,000 in rewards have been offered for information leading to their arrests and convictions.
Stow is listed in critical condition with brain injuries after being kicked in the head during the assault.