DiGiulio is best, but in a tough test

FOUNTAIN VALLEY — Newport Beach’s Joseph DiGiulio is the No. 1-ranked tennis player in the country in boys’ 12 singles.

But even at such a young age, DiGiulio knows that any good tennis player’s game is a work in progress. Even the best have to keep striving to get better.

And even with all his skill, DiGiulio proved Friday at the 105th annual Southern California Junior Sectionals that he can grind out a win when he needs to. That’s what he did in the Round of 16 against No. 6-seeded Edward Kim of La Habra, taking a 6-4, 6-4 victory at Mile Square Park.

DiGiulio advances to today’s quarterfinal against Thien Nguyen of Long Beach at 2:15 p.m. at Mile Square. But that outcome seemed in doubt for much of his match against Kim.

DiGiulio’s opponent came out aggressive, breaking him in the first game of the match. Kim then held his own serve to take a 2-0 lead.

“A lot of times they go out hitting,” said DiGiulio, who turned 12 on June 16. “They don’t have any fear; they just want to take you out.”

DiGiulio, who won the 14s division at the Santa Barbara Summer Tournament two weeks ago, also won the 16-and-under draw at a Laguna Niguel tournament last week.

Tournaments like these are the reason why he’s unseeded at sectionals, having not played enough 12s matches in Southern California this year, his father, Paul, said.

“You’re going to play the people eventually in the tournament,” Joseph DiGiulio said, shrugging it off. “I feel comfortable against everybody, because I know I can beat everybody. If I was playing [more at 12s] then I’d really be the No. 1 seed.”

But DiGiulio has to be the most dangerous unseeded player out there.

Still down to Kim at 3-4, he won three straight games to capture the first set, including a break at love in the final game.

“I started playing better as it went on, but I was still playing too defensive,” DiGiulio said. “I was just hitting the ball too short a lot of the time. I just need to get more aggressive.”

He did in the second set, even after Kim took a 3-2 lead. Again, DiGiulio took three straight games to jump ahead, 5-3, and eventually won the match.

That aggression is something DiGiulio’s coach at Irvine-based Advantage Tennis Academy, Mahmoud Karim, is trying to encourage.

“Joseph’s been winning by just keeping every ball in play, running down everything,” Karim said. “He knows how to hang in there longer and has a lot more persistence than other players. The next step for him is to take his consistent game and make it more aggressive.”

Still, it’s not a bad problem to have for DiGiulio, who won has won the boys’ 10s division at junior sectionals.

Last year, he lost in the 12s semifinals and finished in fourth place.

“Taking the next step to generating winners, picking up the pace and taking more risk, that’s kind of new territory for him,” Karim said. “He does it in practice and on and off in matches. But when it gets tight, he still pulls back … He doesn’t like the idea of making a mistake. He has to come to realize that it’s all right to make mistakes.

“It’s a tough step, but he’s already learned so much by being consistent and persistent. It’s just going to help him grow through the rest of his tennis career.”

MATT SZABO may be reached at (714) 966-4614 or at matthew.szabo@latimes.com.