SACRAMENTO, Calif. — A California legislative committee advanced a bill Wednesday that would place a two-year moratorium on the use of metal bats in high school baseball to allow for a safety review.

Supporters said metal alloy and aluminum bats make baseballs travel faster and lead to more serious injuries. Opponents of the moratorium said wooden bats also are dangerous.

The bill moved forward on the same day a 16-year-old pitcher for Marin Catholic High School, who was struck in the head by a line drive hit off an aluminum bat, was released from a rehabilitation hospital.

The March incident left Gunnar Sandberg with a traumatic brain injury.

His father Bjorn Sandberg said Gunnar had been in a coma for weeks and was happy to be recovering at home.

"He's made really tremendous improvement," Bjorn Sandberg said in a telephone interview, adding that Gunnar will be returning to the hospital for rehabilitation therapy several hours every day.

Gunnar's family had planned to attend the bill hearing in Sacramento but changed their plan when they learned their son was coming home.

"We are totally supportive of anything that will make the sport safer so others don't have to live through what Gunnar and the family have had to go through," Bjorn Sandberg said.

The legislation, introduced by Assemblyman Jared Huffman, D-San Rafael, passed the Senate Education Committee.

The bats already are banned in New York City, Huffman said.