Martina Hingis' remarkable tennis comeback could test the endurance of Jun Hernandez.

Hingis hired the University of Hawai'i Rainbow Wahine coach to be her hitting partner at this week's Acura Classic in San Diego. Hingis, ranked 13th in her first full year back after some three years out of the game, became the first player to reach the third round Tuesday.

Hernandez also served as a hitting partner for Anna Kournikova and Conchita Martinez before taking the UH job in January. He initially hooked up with Hingis through a mutual friend but hadn't worked with her since injuries took her out of the game the summer of 2002.

"She remembered me so that's a good thing," Hernandez said. "It says a lot. She likes the way I do my job."

Hernandez has been coaching since 1997. He graduated from San Diego State in 1995, where he played No. 2 singles for UH men's coach John Nelson. He rarely plays competitively now, but his team apparently keeps him fit enough for a five-time Grand Slam singles champion. Hingis also won this year's Australian Open mixed doubles title.

Hernandez figures Hingis' unexpected offer can only help Hawai'i. The money he gets paid for helping her is not bad either.

"A lot of the top juniors played in qualifying here so it's a very good tournament for me to watch," Hernandez said. "Also, being out there hitting with Hingis gives me a good in when I'm recruiting kids.

"Just imagine a top junior tennis player looking at me with my UH shirt and hat hitting with the world's former No. 1."

Hingis, 25, has won 41 titles and more than $19 million since slashing her way into the public eye in 1993. She became the youngest Grand Slam champion in the 20th century when she captured the Australian Open at 16 and was ranked No. 1 at the end of 1997, '99 and 2000.

She is immortalized in wax at Madame Tussaud's in London, was the first female athlete to be on the cover of GQ magazine and was Associated Press Female Athlete of the Year for 1997.

Five years later she slipped out of the top 10 for the first time in eight years as injuries and the birth of "Big Babe" tennis beat up her small frame. She announced she was taking an "indefinite break" in 2003.

Hingis returned part-time last year, re-appeared in the rankings after Australia and was back in the top 50 by February.

"I'm happy she's back into tennis because she plays a different game," Hernandez said. "She is so smart on the court. I wouldn't do this for anybody. I learn from her — how she works, how she thinks out there.

"She doesn't just hit it hard, it's like a chess game. She's always looking for weaknesses. That's how she does it."

Hingis' mind-over-matter strategy is probably why her comeback has been so successful. She is still quick, with exceptional anticipation and versatility. But the best part of her game remains above the neck. That only gets better with age.

"Before the other person hits the ball she is already in position," Hernandez said. "She's been doing it how long now ... since she was 3? She won the French Open Juniors at 12. That says a lot. When you're 12 playing against somebody 18, you can't overpower them."

Hernandez will return to Hawai'i in 10 days and hopes to have at least four new players on his roster next season. The Rainbow Wahine, who haven't had a winning season since 1999, were 4-18-1 last year.

Sabita (Maharaj) Walkup has already committed to UH for her senior season. Walkup was an All-American with a top-30 ranking at Tennessee. She graduated in three years, married Schofield's Frank Walkup and moved here earlier this year. Walkup won this year's Hawai'i Sectional title.

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