CHICAGO — When Miami Marlins outfielder Curtis Granderson raced into foul territory to catch a fly ball just before reaching the knee-high wall at Guaranteed Rate Field, he might have tumbled into the lap of 7-year-old Nathaniel Wolpoff.
But not on Monday night.
Granderson — and the wispy, sports-goggled Nathaniel, who was sitting in the first row with his parents — were spared any calamity by a new feature at the White Sox’s home ballpark: protective netting that extended all the way from behind home plate to each foul pole.
Such extensive netting, installed to save fans from searing line drives more than tumbling outfielders, is the first of its kind in Major League Baseball.
It will not be the last, as the sport comes to grip with a spate of serious fan injuries caused by foul balls. The Washington Nationals also extended their netting to deep down the foul lines before Monday’s game, which was rained out. The Pittsburgh Pirates, the Kansas City Royals and the Los Angeles Dodgers have pledged to push their netting to the foul poles. The Texas Rangers will do so in their new ballpark that opens next season.
“At least we can be first at something,” said Judy Wallenstein, a long-suffering White Sox fan who watched the game with her husband, Roger, from their usual seats near the third-base line.
The movement to bring even more protection to big-league ballparks has been spurred by increased attention on a series of serious injuries recently, including when a 2-year-old girl was struck by a line drive at a game in Houston in late May. She sustained a fractured skull, bleeding on the brain and seizures, according to a lawyer representing the family.
The images of Albert Almora Jr. of the Chicago Cubs, who hit the ball, weeping and holding his head in his hands after the hit drew renewed scrutiny on fan safety and calls for more protection.
The accident in Houston may have seemed like an outlier, but it’s an increasingly routine occurrence at major-league parks. Over the weekend, a 3-year-old boy was taken to the hospital in Cleveland after being hit by a line drive, and fans were struck in consecutive games at the Tampa Bay Rays’ stadium on Friday and Saturday — one in the head by a ball and the other in the back by a bat that sailed over the netting.
M.L.B. Commissioner Rob Manfred has resisted mandating more netting for every team or giving teams a deadline, choosing instead to leave the decision to individual teams, even as players have almost universally asked for a safer environment for fans.
All teams fulfilled Manfred’s request to extend netting to the far end of the dugouts before last season, but only after a young girl was seriously injured after being struck by a ball at Yankee Stadium late in the 2017 season.
Manfred, who declined to comment for this article through a spokesman, told reporters on June 20 that he was satisfied with how teams were proceeding. But Illinois’s two senators, Dick Durbin and Tammy Duckworth, were not. A week after Manfred spoke and one day after the Houston girl’s injuries were disclosed, the senators wrote a letter to Manfred urging him to compel teams to do more.
Durbin considers himself a baseball traditionalist, once taking the floor of the House of Representatives to preach about the sanctity of the wooden bat — and rail against the designated hitter and the lights at Wrigley Field. But watching a 2016 episode of HBO’s “Real Sports” that detailed several serious injuries to fans hit by foul balls got his attention.
“You don’t think that much about it because it seems so rare,” Durbin said in a phone interview. “It turns out it’s not that rare. The game has changed.”
He added: “The last time I was at Wrigley, in an exposed section with no netting, I thought, would I really bring my grandkids to this game? And the answer was no. I just wouldn’t do it until I felt like I had a safe place for them to sit.”
More and more data has shown that baseball games are increasingly dangerous for fans who sit near the field. Not only are pitchers throwing faster and batters swinging harder than ever, but more of those balls are being hit into the stands.
The website FiveThirtyEight found that nearly 14,000 more foul balls were hit last season than in 1998, when M.L.B. expanded to its current 30 teams — and that the hardest hit balls are reaching seats that are not protected in most stadiums. In tracking data from 580 foul balls this season, FiveThirtyEight found that every line drive with a recorded speed off the bat of more than 90 miles per hour landed in an area that was unprotected by netting.
The White Sox said they began considering extending their netting in May, before the accident in Houston or another one at their stadium in early June in which outfielder Eloy Jimenez struck a ball that left a woman bloodied and on her way to a hospital. The team owner Jerry Reinsdorf told his top executives to find a solution.
“It is not one incident,” said Howard Pizer, the team’s executive vice president. “There were just more and more incidents we were reading about. It’s just an idea whose time has come and we needed to do something.”
The White Sox extended netting by running the cable holding the nets to each foul pole, 210 feet in right field and 205 in left, and attached three additional guide wires to the second deck to secure it. No poles were required to support the netting, which is the same green-tinted mesh that is behind home plate.
There were additional ground rules: Treat the new netting like a wall; if a foul ball hits the net, the play is dead; if a fair ball hits it, the play is live. But they were so simple that the umpiring crew canceled a pregame meeting to go over them.
Not every ballpark may be so simple. Kevin Uhlich, the Royals’ senior vice president for business operations said it would take a week for engineers to devise plans, three weeks for the netting to be delivered and another week for it to be installed — though some of those steps must be taken when the team is on the road. The Royals hope to have pole-to-pole netting installed in August.
“There are things you have to work through,” Uhlich said. “Some fans don’t realize you can’t just tie something up somewhere.”
Still, the White Sox fans seemed largely accepting on Monday night, even if some did not particularly care for the new obstruction. Rick Aspan, a 20-year season ticket holder whose seats are in the front row on the third-base line, said the netting, which was inches from his face, left him feeling “like an animal in a cage.” But he said the team had done the right thing.
Curtis Wilson, who sat with his wife and 5-year-old daughter in the sixth row, said he could enjoy the game without worrying about their safety. Nearby, 11-year-old Ellie Vantholen said the view was fine. “The only thing that blocks my view is people’s heads,” she said.
For young Nathaniel Wolpoff, the game was the final stop on a vacation that began with the All-Star Game in Cleveland. He has now been to all 30 major-league parks with his schoolteacher parents, pilgrimages they began making four years ago from their home in San Diego.
So when Granderson caught the fly ball up against the netting and asked, with a smile, if Nathaniel was O.K., he had no problem saying yes.