Rolling Out the Red Carpet : In-line skaters will be welcomed to Orange County Marathon for the first time Sunday. And they’re expected to burn up the course.

Race organizers expect the top finishers in Sunday’s Orange County Marathon to complete the course in well under 1 1/2 hours.

Not the runners, of course--after all, the fastest marathon ever run was just under 2 hours, 7 minutes. It’s the in-line skaters, zipping along at speeds up to 28 m.p.h., who will be burning up the course Sunday.

The Orange County Marathon will be the first ever to include a special division for in-line skaters, according to organizers. The Rollerblade Marathon (sponsored by the sport’s biggest manufacturer) will begin at 7:05 a.m. at Anaheim Stadium, the same time as the wheelchair race. The running marathon begins at 8 a.m.

After winding through six county cities, the 26.2-mile course ends on Campus Drive across from UC Irvine.

Advocates say the marathon is another sign of the growing acceptance of in-line skating as a sport. In the past, in-line skaters have joined running marathons informally or been banned altogether. Jim Rosasco, a skater with Team Rollerblade, says he hopes this is the beginning of a trend.

“I think it’s a good distance for skaters because it can be done in a relatively fast time,” Rosasco said. “It makes for pretty fast racing, yet there’s enough time for tactics to fit into the race.”

“It’s a great idea. It’ll introduce runners to in-line skating,” said Tom Peterson, founder and president of Hyper Corp., a Huntington Beach-based maker of premium skate wheels. Also, he added, “Orange County’s perfect for it,” with the climate and the flat course.

In-line skates, which emulate ice skates by putting the wheels in a straight line, have been a common sight along Southern California’s beaches for several years. Now, these items of trendy beachside accouterment are at the center of a growing competitive sports craze.

That makes sense. The skates were first introduced as a way for ice-skaters and hockey players to stay in shape off-season, and they’ve been adopted as cross-training tools by cyclists, skiers and other athletes. Now, in-line skating is developing its own competitive events and its own slate of professionally sponsored teams.

The sport’s first national championship, also sponsored by Minneapolis-based Rollerblade, was held last year in the parking lot of the Great Western Forum in Inglewood and drew about 400 competitors. This year’s edition of the event, held earlier this month in Irvine, drew about 1,500 racers.

Ten kilometers is the sport’s most popular distance now, performed either on a closed loop or on a road course. But there are other competition distances, including 30, 50 and even 100 kilometers. At this stage in the sport’s evolution, racers tend to compete at several distances rather than specialize in a single event.

Also, in-line skate racing still tends to attract competitors crossing over from other sports: conventional roller skating (a professional sport in much of the world), ice speed skating, skiing, running and cycling. Current stars of in-line skating include ice speed skater Eric Flame, silver medalist in the 1988 Winter Olympics, and biathlete Terry Martin.

“It’s really growing fast, and you’re getting athletes going into it from other sports,” said Rosasco, who has been a professional mountain bike racer for five years, but is now spending more time on the in-line skating circuit. “If you have a good aerobic base, you could be a very good in-line skater.”

“There are a lot of people with the fitness level to be competitive at in-line skating,” said Jim Essick, Cypress-based regional manager for Rollerblade. “The sport is so new, they’re still able to get in there and do pretty well.”

The best skaters are on the factory-sponsored teams, such as Rollerblade, Kryptonics and Hyper, according to Essick. They compete for increasingly lucrative prize money and sponsorships. While the actual technique for in-line skating is similar to ice speed skating, the team tactics are modeled after road cycling.

Team in-line skaters ride in packs, draft and even block for a designated skater who breaks from the pack and “goes off on a flyer,” Essick said.

Most competitors still race on an individual basis, though. “This is a sport where you can go out just like running and race against the clock, go for your personal best,” Essick said.

Peterson, of Hyper, was a seven-time world speed amateur champion on conventional roller skates before he retired from competition to start his business, so he has a double interest in the rise of in-line skating.

Many of the racers from other sports started using in-line skates primarily as a training tool because the skates offer an aerobic workout without putting a lot of stress on knees and ankles. But “because they’re athletically inclined, they want to test themselves,” Peterson said.

Now, many of the athletes are choosing skating over their previous pursuits.

“The racing circuit’s growing really fast,” he said. “The sport’s just going crazy.”