When the six-ounce frozen rubber puck leaves Al MacInnis's stick, it often travels faster than a Randy Johnson fastball. When he really cranks one up, it's known as hockey's "radio shot" -- you can hear it, but you can't see it.

More times than the St. Louis Blues defenseman can count, his faster-than-fast slap shot has deflected off a player, the goal post or a stick and slammed into the unprotected crowd, destination unknown. Sometimes, the result is frightening.

Mario Lemieux, the Pittsburgh Penguins' owner and Hall of Fame center, says nothing quiets players on the ice more than the sight of a puck flying into the stands. He's seen broken noses, bloodied faces and terrified children, and wondered if something couldn't be done to protect hockey's greatest asset: its fans.

That's why MacInnis and Lemieux were among the scores of players who cheered when the NHL ordered protective netting installed in all arenas this season.

"I think it's going to be great for the fans," Lemieux said. "The puck travels so fast, sometimes there's no time to react."

The move came in response to the death of 13-year-old Brittanie Cecil, who was struck by a deflected shot at a Columbus Blue Jackets game -- the first known spectator fatality of its kind in league history.

Many fans at preseason games are still adjusting to the black, knotless netting, which stretches an average of 30 feet high along the end boards to just beyond the goal lines. Because it covers a far larger area than the netting behind home plate at a baseball game, it affects the sight lines of thousands at every game.

Some say the NHL overreacted.

"I don't like it," Mike Menigno, of suburban Pittsburgh, said at a Penguins game. "Some people who were here at the last game are looking into getting their seats changed."