Serve’s Up at Malibu for Stewart

For eight exhausting minutes, Doug Stewart hit backhand and forehand volleys on his backyard tennis court near Zuma Beach in Malibu.

With each powerful stroke, his breathing became heavier and his heart beat faster. His T-shirt went from dry to soaking wet.

Few 17-year-olds in any sport could put together the sustained bursts of energy displayed by Stewart, the No. 1-ranked high school tennis player in Southern California.

To think he was engaged only in a short workout with his father, Forrest, reveals plenty about Stewart’s drive to succeed in a sport in which mental toughness is as important as physical ability.

“I think it came naturally, the competing aspect, fighting for every point,” he said. “I just like the aspect, me versus him, and who’s going to blink first. I feel confident when I’m out there. I can out-compete anyone.”

Stewart, a senior at Malibu High, has been ranked No. 1 for his age group in Southern California by the U.S. Tennis Assn. at 10, 12, 14, 16 and 18. Last season, he won the Southern Section individual championship.

He signed with Virginia last fall, turning down Stanford, UCLA, USC, Princeton and Pepperdine. He’s a straight-A student who scored 1,370 on his SAT. His older brother plays tennis at Princeton and his younger sister is a freshman tennis player at Malibu.

His father played tennis at UCLA and is a respected coach who trained his children to be good players and also good citizens.

“I’ve raised them to be individuals and rise up and make a difference,” Forrest said.

Stewart, 5 feet 10 and 160 pounds, has a 115-mph serve, an aggressive two-hand backhand and strikes the ball so hard that opponents trying to return volleys struggle if they don’t stay alert.

Last year, Stewart would rise at 5 a.m. and head to Pepperdine with his brother to lift weights under the direction of a private trainer. He’d pass his friends going to the beach to surf before school.

“They said I’m crazy for lifting weights that early in the morning, and I say, ‘You’re crazy for surfing that early in the morning,’” Stewart said.

Stewart and his father have been adamant about not making tennis a 24-hour-a-day obsession. Rather than spend weeks away from home traveling to international tournaments, Stewart turned down tournaments to stay in school and maintain a sense of normality during his teenage years.

His academic success has enabled him to have a fallback plan if his goal of playing professionally doesn’t work out.

In 1998, he did travel to Japan to represent the United States in the Junior Davis Cup, an experience he’ll never forget.

“It was great to play for your country and not just you,” he said. “It gave me the belief I could do this.”

Stewart has been playing since he was 6. He used to play against his brother, Steve, in the backyard after school in matches that both took as seriously as if they were playing at Wimbledon.

“It was a death match,” Stewart said. “Neither of us wanted to lose and we’d go at it.”

Playing against Stewart requires intense mental discipline. He attacks and never lets up, priding himself on his steady, stoic demeanor.

“I don’t have a lot of highs and lows,” he said. “I keep constant pressure on my opponent.”

Stewart said he disagrees with those expressing concern about the lack of American successors to the likes of Andre Agassi and Pete Sampras in men’s tennis.

“They were saying the same things after [Jimmy] Connors and [John] McEnroe retired,” he said. “All of a sudden, Agassi, [Jim] Courier and [Michael] Chang came up. There are a lot of players who will replace the Samprases and Agassis.”

Stewart could be one of those future American standouts, and he’s not afraid of the commitment needed to succeed.

“It’s a lot of hard work,” he said. “You need a good coach, but it comes from the desire to do it. You have to get out there and play. The winning part is fun, but the working part is fun, too. When I’m out there, I’m not thinking about the pain in my legs. I’m thinking if I get this shot right, I’m going to do more winning.”

Eric Sondheimer can be reached at eric.sondheimer@latimes.com.