There is nothing routine about Rio Mesa High's arrival to the Division II baseball semifinals.

Although coach David Soliz would like to think it's the routine fundamentals that have made a difference in a tale of two halves of a season.

Home for only the second time in the playoffs, Rio Mesa (16-10) faces Vista Murrieta today at 3:15 p.m. for the right to advance to Thursday's 7:30 p.m. championship game against either Camarillo or Oxnard at Dodger Stadium.

Rio Mesa hasn't advanced to a baseball final since 1986, when the Spartans won a section championship for the fourth time in seven years.

For the first 13 games, Rio Mesa looked anything but a championship contender.

Not only did Rio Mesa have a sub-.500 record (6-7), it allowed 10 or more runs five times, including blowout losses of 16-3, 10-1, 11-2 and 16-1. Erratic defense and little run support were culprits.

In a reversal of fortunes, Rio Mesa has held opponents to two or fewer runs seven times in winning 10 of its last 13 games.

After making five errors in his first three games, sophomore second baseman Chase Crawford has not mishandled a play since.

In Friday's 3-2 quarterfinal win over Crescenta Valley, left fielder Randy Cervantes caught up with a fly ball in foul territory after a sprint from left-center field.

"The kids are making the routine and the not-so-routine plays," said Soliz.

Cervantes, center fielder Ralph Robles-Rivas and right fielder Joe Ramirez have turned potential extra-base hits in outfield gaps into long and quiet outs.

Soliz sees the run-saving plays on the field are counting toward lower pitch counts and fewer at-bats for opposing teams.

"Baseball is an offensive game," said Soliz. "Our guys take pride in making good defense."

When Rio Mesa was down in the darkest period of its season, Soliz brought his club together.

"We made a concerted effort to do the basics putting the ball in play, running the bases well and making the routine defensive plays that we had gotten away from," he said. "We made it a point to get back to the fundamentals. We tried not to complicate it. For a period of about a week, we refocused and things came back."

With No. 1 starting pitcher Jordan Lindebaum (10-3) on the mound, the team's confidence level was rarely lacking.

Now it's there for whomever Soliz sends out to the hill.

The second-half run has given Rio Mesa baseball faithful promise for the future.

Five of Rio Mesa's starters in the quarterfinals were either freshmen or sophomores. Freshman Michael Griffith has been the starting catcher all season. Sophomores Crawford and Cervantes have been regulars. New to the lineup in the closing weeks has been sophomore third baseman Shawn Barber, who had two hits against West Torrance and Upland.

The only senior position starter is Alex Ramirez, who leads the team with a .436 batting average.

Adding up: Love it or hate it, the Oaks Christian athletic program continues to build impressive credentials.

With titles this spring in boys' swimming and volleyball, the school's teams have won 19 section championships over the last five years.

The football program owns four consecutive CIF titles. Girls' soccer, boys' volleyball and boys' swimming have won three championships. Eight of the school's programs have won one or more titles.

County record: The Thousand Oaks baseball team bettered the 14-year-old county record for most doubles in one season.

The Lancers had 73 doubles, passing the mark of 71 set by Simi Valley in 1993. Six players had seven or more doubles, including 13 by Jett Bandy.

Thousand Oaks had 289 hits, eighth highest in county history, and tied a school record with 25 wins (25-5-1).

Matt Bywater finished 12-0, setting a school record for most wins in a season. He is only the sixth pitcher in county history to win 12 or more games without a loss in a season.

Derry Eads' e-mail address is deads@VenturaCountyStar.com.