For card club regulars, it's both business and pleasure.

Pacing nervously outside the front doors of the Commerce Casino, Rick Martinez inhaled deeply on his Marlboro Light and pondered his luck. The day, he acknowledged, was not going well.

After seven hours at one of the card room's high-stakes poker tables, Martinez was down $700 - not a particularly daunting sum for a high roller out on the town, but Martinez is no such high roller. Unlike most card players, he doesn't gamble for kicks. He gambles for a living.

A 42-year-old former accountant, with a wispy brash of a moustache and dark, darting eyes, Martinez said he has been earning his keep at the Commerce Casino's card tables for the past four months.

"I'm just an amateur," he said, comparing himself to the scores of professional players he competes against every day.

Still, that didn't keep him from once leaving the club with a cool $3,500, his best day ever. And yet, there was the day he dropped $1,800. "You have to have a budget and you have to have discipline," Martinez said. "And you have to know when to get up and leave."

Apparently, that moment had not yet come. Taking a final drag on his cigarette, he stamped out the butt beneath his boot and headed back inside. He put his name on the list for a seat at a $20-$40 poker table in The Terrace, the casino's top poker section, and waited for a chance to win some of his money back.

With 200 tables and $110 million in annual revenues, the Commerce Casino is the state's largest card room. An estimated 3,000 people walk through its doors every day. On weekend nights, players can expect long waits at the club's most popular gaming tables.

Brightly lit with crystal chandeliers, decorated with palm trees and pastel prints for a faux tropical theme, the casino's green felt tables are packed with gamblers playing poker games - stud, hold 'em, lowball and Omaha hilo split. In the adjacent "California" room, a younger, mostly Asian clientele noisily shakes dice canisters and shout out for good fortune in such fast-moving Asian games as Pai Gow and Pan.

In the midst of it all, waitresses in short skirts negotiate the maze of tables balancing trays of drinks. A pair of snack bars sells deli sandwiches or sushi trays. And of course, there's a dinner buffet, offering that Las Vegas staple - prime rib - a bargain at $8.95.

Still, even when the action is at its hottest, it would be difficult to mistake the Commerce Casino - or any of L.A. County's seven other card rooms - for their Nevada counterparts. For one thing, the incessant clang and drone of slot machines and other electronic gambling devices is conspicuously absent. Such machines are outlawed in California, as are other games of chance, such as roulette and crops. You can play blackjack, but playing "21" also is prohibited by state law; casinos wiggle around that by reengineering the rules slightly, such as playing to 22 instead.

But if gambling in California remains a shadow of that in Nevada, it doesn't appear to bother most of the Commerce Casino's customers.

"I have more control over the game here," said Martinez.

He was referring to California's ban on Nevada-style house-banked games. In the state's card rooms, gamblers instead play against each other; the casinos make their money by charging players a fee to sit at the table.

A high-stakes player like Martinez will pay $12 an hour for the privilege of playing; gamblers at less expensive tables will pay as little as 25 cents a hand.

Martinez still goes to Vegas once or twice a year, but mostly for the spectacle. When it comes to winning his rent money, he prefers playing right here in L.A.

And he's not the only patron who prefers Los Angeles to Las Vegas.

"I gave up Vegas when this place opened up" in 1983, said Victor Dee-Mash, a 54-year-old insurance salesman from Hollywood, waiting for a seat at a $2 hold 'em table.

Dee-Mash said he used to drive to the desert at least six times a year. He played poker at the Tropicana - where, like many regulars, he was given free lodging in the casino's hotel.

But with the Commerce Casino an easy detour on his evening commute, the five-hour journey to Las Vegas is nothing but a chore. Besides, he prefers the laid-back attitude of LA.'s clubs, Now, he gambles in Commerce a couple of times a week.

"I can't afford any more than that," he said with a laugh. "But I like the friendliness of this place. For a couple of hours, it's a great way to unwind."

For David Holm, another Commerce Casino patron, those stakes are way too high. The 32-year-old barber from Upland has a much more modest goal - to win enough to pay for dinner and a couple of drinks for himself and a friend.

"I like to hang out here," said Holm, who travels to Commerce about once a month. "And the food is pretty good."

Holm's name was called by a tuxedo-clad floor monitor - a seat had opened at a $2 stud table - and he excused himself. But he wasn't gone long. After three quick hands, he returned with a stack of chips. He'd won $38.50 with a straight. "Dinner is paid for - it's on them," he said, gesturing toward his competitors as he walked over to the cashier window to redeem his winnings.

Not all players were so fortunate. After playing stud poker at a $4-$8 table for just 90 minutes, Jim Romane already was down $200 and only had $60 left to win it back. He decided to take a break, have a smoke, and mull his strategy.

"It goes up, it goes down," he said. "Who knows? I can come back and win it all back tomorrow."