Even before the sun shone over the field at Fenway Park, hurling fans watched their favorite Irish players train in the rain before the 2017 Hurling Classic and Irish Festival on Sunday.

Four well-known hurling teams — Galway, Clare, Tipperary, and Dublin — competed in Boston for the Players Champions Cup. Hurling, one of Ireland’s national sports, is a fast-paced game of agility that’s been played on the island for thousands of years.

Hurling looks like a blend of hockey and lacrosse. The players donned helmets and, with their curved hurling sticks, chased a small, hard ball called a sliotar down the field.

David Burke, 27, the Galway hurling captain and a four-time All-Star, said the game is all about hand-eye coordination. “It’s a real intuitive reaction kind of game,’’ said Burke, whose team was 2017’s All-Ireland hurling champion. “You have to decide in split seconds.’’

“Hurling is kind of a national secret outside of Ireland,’’ said Michael Verney, public relations officer for the Gaelic Players Association.

Verney said the Fenway event was a way to promote the sport and appeal to a new audience. Nearly 28,000 people came Sunday to watch three 40-minute hurling matches (Clare beat Galway in the final, 50-33), as well as to enjoy Irish music, food, and dancing.

Fans sported Patriot and Red Sox beanies and wore green or in Pierce McDonnell’s case, a bright neon wig.

“It’s great to be here and see my home team play,’’ said McDonnell, who moved to the United States from Dublin 30 years ago. “I can cheer ‘Dubs’ once again.’’

Merrill Bloor of Plymouth enjoyed a cold beverage with her husband before the match. “I’ve watched [hurling] on TV, I’ve studied it, I’ve never seen it in person,’’ said Bloor. “Also, I love anything to do with Ireland.’’

Though 15-year-old Catrina Looney’s grandmother was from Galway and her grandfather was from Clare, the Burlington teen said she had to cheer for Galway because they were the favorites.

Looney had been at Fenway two years ago, the last time a hurling match graced the field.

“It was one of the best experiences ever,’’ Looney said. “. . . There was a big fight that happened.’’ Plenty of brawls broke out Sunday, too. It comes with the territory, said Sean Mahoney, a Worcester resident and local hurler who’s played the game for years.

“No matter how hard you fought on the field, you usually get together for a beer afterwards and talk,’’ Mahoney said. “After the game, you’re friends. On the field, you’re bitter enemies.’’

Cristela Guerra can be reached at cristela.guerra@globe.com. Follow her on Twitter @CristelaGuerra.