It makes perfect sense that University of Hawai'i head softball coach Bob Coolen, despite a to-do list filled with crossed-out items, still is not satisfied.

The Rainbow Wahine entered this season with three goals: Earn a high seed in the Western Athletic Conference tournament, win the tournament, and amass at least 40 victories.

With 17 games remaining, beginning with tonight's WAC game against Louisiana Tech, the Rainbows are 30-7 overall and 3-0 in the WAC.

While acknowledging "our goals are in sight," Coolen still frets. That should be expected from a perfectionist who vacuums his office regularly, serves as the lead grounds keeper at Rainbow Wahine Stadium and has turned spring cleaning into a year-round activity.

"We're ahead of the curve, but we can't be satisfied," Coolen said. "We want to do well in the WAC. We can get to 40 wins, but that won't mean enough if we don't finish high in the WAC."

The Rainbows defeated four teams that were ranked — Oregon State, Baylor, Nebraska and Auburn — and have victories against regional opponents Cal State Northridge, Colorado State and Utah.

"There are no guarantees" for an NCAA regional berth, Coolen said. "Not unless you're Fresno State."

The Bulldogs have qualified for every Regional since the format was implemented in 1983.

The Rainbows have won six in a row — including five against Nevada, of which three counted in the WAC standings — and are 18-5 in March.

The keys are strong pitching and the ability to adjust the lineup.

When right fielder Tanisha Milca suffered a fracture in her right hand last week, Richie-Anne Titcomb stepped in as the leadoff hitter. Milca, who will miss another two weeks, has more power (eight homers), but Titcomb has a better average (.310).

Freshman Katie Grimes also has emerged as the full-time catcher. A few weeks ago, a buddy system was set up in which Grimes was Kate Robinson's catcher, and Stacey Yamada worked with Justine Smethurst.

"Katie is starting to feel more comfortable," said Coolen, noting Grimes also has improved her hitting. Grimes had the game-winning hit in the opener of Tuesday's doubleheader against Nevada.

Coolen said Smethurst will start tonight against Louisiana Tech. Smethurst did not lose her status at the staff's ace despite struggling against Nevada.

"Nevada has her number," Coolen said. "You would hope someone could beat every team, but sometimes that's not the nature of the beast."

Robinson will pitch in tomorrow's doubleheader.

Reach Stephen Tsai at stsai@honoluluadvertiser.com.