Dynamic Duos Take Different Roads to Top : Volleyball: Kirby and Rock got together at last minute, and Kotas and Castro trained together during off-season. Both teams are in semifinals at San Diego Open.

SAN DIEGO —  All that sweat was time well spent.

For the two teams who have met in four of the Women’s Professional Volleyball Assn.’s six championships, there was a whole lot of preseason sweating going on. All for good reason.

* Karolyn Kirby sweated out partner Jackie Silva’s return from Brazil, wondering what kind of shape Silva would return in. There was also that little matter about Silva rejoining the national team.

* Angela Rock sweated out the timeliness of Rita Crockett’s return from Italy’s indoor season, where postseason play would further delay Crockett’s arrival for the beach season.

* And Lori Kotas and Gail Castro just plain sweated.

Logistics was the most logical but hardly the only reason Kirby eventually joined forces with Rock--both reside in San Diego--to form what has become the team of record on the beach. Together they have won four 1991 WPVA events, including the last two, with no indications of slowing down.

Meanwhile, Kotas, who lives on a boat in San Diego, and Castro, of Carlsbad, have been sentimental favorites--some would argue fools--who have remained joined at the hips for four seasons with no titles--until this year. An off-season of unprecedented training culminated in a tournament victory in Week 4, in Fresno.

Kirby-Rock and Kotas-Castro. After they swept their three matches apiece Saturday, fans will have to decide which hometown players to cheer when the semifinals of the San Diego Open get under way at 9:30 a.m. today in Pacific Beach.

Should they win their semifinal matches, top-seeded Kirby-Rock against Linda Carrillo and Liz Masakayan and second-seeded Kotas-Castro against Janice Opalinski-Harrer and Elaine Roque, this won’t be the anticipated hometown showdown expected, according to Kirby.

“(Angela and I) talked about that,” said Kirby, the tour’s MVP last year. “This is really important for us, but not because we’re looking at it as a hometown tournament we have to win. That’s added pressure we don’t need. That’s not part of game plan. We want to break that barrier of two (victories) in a row. We’ve done it twice. Can we win three?”

Not if Kotas and Castro, who have had more top finishes in the first quarter of this season than in all of 1990, can help it.

Although they’ve only won one tournament, Kotas insists the taste of victory is too sweet to experience just once.

“We’re just not happy to be (in the championship),” she said. “Instead of hanging out and being happy to be there, we want to win now that we know we can do it.”

Not long ago, they weren’t entirely sure they could. As the longest running twosome on the tour--Nina Matthies and Roque split up after losing in the season opener--there was a lot of second-guessing as to why they endured despite the absence of titles.

“We were sick of hearing ‘How do you stay together?’ ” Kotas said. “It was like a 2-ton weight was taken off. We cut the chain we’ve been carrying around so long. We deserve to win. We put way too much work in not to.”

In October, Kotas and Castro began a grueling off-season of daily workouts consisting of three hours on the beach and three in the gym. They also put together a “team,” including a nutritionist, a conditioning coach, a chiropractor and coach Hillary Johnson, who often travels with them.

“Things are different this year for us,” Kotas said. “Seeing the commitment we both made and the hard work, I have a new respect toward Gail. And she saw the commitment I had. Before, we’d do everything on our own. But when you do it together, you see the hard work pay off.”

The quick ascension to stardom for Kirby and Rock contrasted the teamwork of Kotas-Castro. By the time most teams had been formed, they still were training solo.

“I was a little nervous,” said Kirby. “Here it was, two weeks before the season opener, and I had no idea who I was playing with.”

But there were hints. When Silva informed Kirby that she needed more time to heal her injuries, Kirby already had the wheels in motion.

“I’ve always kept Angela in the back of my head,” she said. “I knew this year she had really come on and had spent the winter in training. I know because she kept calling me to train. Being in San Diego, it was perfect. We decided to see how it goes and reevaluate when Rita got back.”

Guess what? Rita’s back. But you don’t break up a partnership this strong.

After only one tournament, tour member Mary Jo Peppler had said they have all the tools to dominate the beach like Sinjin Smith and Randy Stoklos of the men’s tour. Lack of experience is their sole flaw.

Yet, Rock and Kirby are new to each other only in a beach sense. They were teammates on the national team for three years, where Rock was Kirby’s favorite hitter.

“From our days on the national team, our philosophy’s the same,” Kirby said. “We’re both very motivated and competitive.”

Said Kotas: “The fact that they’re both Olympians, that’ll always give them that little edge. They have that fine tuning that we lack.”

But honestly. Did Kirby really think this team could sustain its dynamite start?

“I knew it,” she said without hesitation. “Of course that’s easy to say after we’ve won four tournaments. But I knew if we could both do what we’re capable of doing and put it together, we’d be a great team. I couldn’t see how anything would stop us. . . . I visualized what she and I could do and I liked what I saw.”

And Rock likes what she’s heard from Kirby, who has had almost a nurturing effect on Rock.

“I’m more mature this year,” said Rock, who works as a fireman. “Part of that may be my job, but a lot of it is Karolyn. She believes in me 100%, and she’s a teacher, but she also respects me and what I have to say. That’s important for me. I need to know I’m a good player.”

Kirby’s encouraging words aren’t reserved for Rock. She spreads them like holiday cheer.

“I can’t even see (losing and splitting up) happening,” Kirby said. “Maybe if we just bombed out. But this is the perfect arrangement for me. I’m happy with Angela. I see nothing but potential and growth.”

Volleyball Notes

No doubt Karolyn Kirby-Angela Rock, Lori Kotas-Gail Castro will have their respective cheering sections today. But Kirby supporters are certainly identifiable. Seen working the crowds Saturday were an assorted number of fans with T-shirts that read: “I Dig Karolyn,” at the top, and “Kirby’s Korner,” at the bottom. . . . Holly McPeak, a member of UCLA’s national champion women’s team, was leading the Flamingo Hilton’s weekly ace contest. By day’s end Saturday she had nine. . . . In former national team member Liz Masakayan and former Olympic silver medalist Linda Carrillo’s first tournament together, they reached the semifinals. . . . Last month tour members Linda Hanley and Jeannie Reeves became mothers for the first time. Saturday, after two weeks of practice, they teamed for their first post-delivery tournament and lost both games, 15-7.