Those in the polo world know O'ahu has a hidden gem in its midst: the Mokule'ia Field, among the most gorgeous in the world, overlooking the beach with the Wai'anae Range rising up behind it.

So when the throngs come out for a day of polo, there's more than a love of horses and the game drawing them.

For some, "it's a sporting event, with games, action, play," said Mike Dailey, president of the Hawai'i Polo Club. "Then, for a lot of people, it's a social event — they organize groups or meet friends. For others, it's a day in the country."

The season began May 6 and continues through the end of September, a total of 22 Sundays. As with most seasons, teams will be visiting, including one from Malaysia.

Dailey said gates open at 11 a.m., and some people make a day of it, showing up early for a swim in the ocean, then setting up a picnic. Games last about an hour, he added, and during halftime, there's an exhibition by Skydiving Hawai'i.

And for those whose polo exposure is limited to the Jason Alexander scene in "Pretty Woman," here's a quick primer from Dailey:

First, think of polo as a mounted version of fast-break basketball. ("People always compare it to hockey, but it's actually more similar to fast-break basketball," he said, because there's no goalie). The positions are fluid like basketball, with a lot of passing of the ball, which is about the size of a softball.

People mounted on horses hit the ball using long-handled mallets.

Don't assume it's an utterly genteel sport like croquet. "It's a sport with danger, with speed, and we do see collisions and falls," Dailey said. "There's a whole structure of rules to the game, like right of way, similar to driving on the highway. ... You can't dive into traffic, but can move someone out."

MOKULE'IA POLO

2 p.m. Sundays, through Sept. 30

Mokule'ia Polo Field (on Farrington Highway, across from Dillingham Ranch)

$8 general, free for children under 12

637-8401

Note: The Honolulu Polo Club, which plays at Waimanalo, opens its season in late June; for information, see www.honolulupolo.com.

GLOSSARY

Bowl in: The umpire starts or resumes a match by rolling the ball down the center of a player lineup.

Bump: A player directs his pony into the side of an opponent's pony.

Check and turn: To slow the pony and turn safely.

Chukker: Term used for period of play in polo.

Flagman: Goal observer; signals by waving a flag over the head if a goal is scored, or below the waist if no goal.

Source: www.SportPolo.com