A fan whose head was bloodied by a broken bat that flew into the stands at Fenway Park on Friday night is in serious condition, her family said in a statement released on Saturday by a Boston hospital.

Tonya Carpenter was struck in the head by the broken bat of Oakland’s Brett Lawrie during a game Friday night against the Boston Red Sox. Boston police initially called her injuries life-threatening. On Saturday, a police spokeswoman later said Carpenter was expected to survive.

The game between the Oakland Athletics and Boston Red Sox was halted in the second inning as emergency crews tended to Carpenter and wheeled her off the field on a stretcher.

“Tonya’s family and loved ones are grateful to all who have reached out with thoughts and prayers but are requesting privacy at this time as Tonya recovers,” said the statement from Beth Israel Deaconess Medical Center Hospital. No other details were released.

Oakland Athletics third baseman Brett Lawrie breaks his bat at Fenway Park. Photograph: Gregory Fisher/USA Today Sports

Oakland’s Brett Lawrie broke his bat on a groundout to second base and part of it hurtled into the stands. Alex Merlis, of Brookline, Massachusetts, said he was sitting in the row behind the woman when the broken bat flew into the seats just a few rows from the field, between home plate and the third base dugout.

“It was violent,” he said of the impact to her forehead and top of her head. “She bled a lot. A lot. I don’t think I’ve ever seen anything like that.”

Police initially called Carpenter’s injuries life-threatening. A department spokeswoman referred all questions on her condition to the hospital on Saturday.

After the game, Lawrie said he hoped the woman would recover.

“I’ve seen bats fly out of guys’ hands in[to] the stands and everyone’s OK, but when one breaks like that, has jagged edges on it, anything can happen,” he said.

Concerned about a rash of flying broken bats and the danger they posed, Major League Baseball studied the issue in 2008 and implemented a series of changes to bat regulations for the following season. Multi-piece bat failures are down about 50% since the beginning of the 2009 season, MLB spokesman Michael Teevan said.

Though dozens of fans at big league ballparks are struck by foul balls each season, there has been only one fatality, according to baseball researchers – a 14-year-old boy who was killed by a foul line drive off the bat of Manny Mota at Dodger Stadium in 1970.

The National Hockey League ordered safety netting installed at each end of arenas after 13-year-old Brittanie Cecil was killed by a deflected puck at a Columbus Blue Jackets game in 2002. She died two days later, and her parents eventually settled with the team for $1.2m, the league and the arena management.