“This year is the first year where it’s been a breath of fresh air for me,” says Los Angeles Sparks guard Kristi Toliver, right, the No. 3 pick in the 2009 draft and a product of the University of Maryland. (Stacy Bengs/ASSOCIATED PRESS)

During her first three seasons in the WNBA, former Maryland all-American Kristi Toliver faced a more formidable adversary than any opponent wearing a different jersey: her own internally corrosive passion.

This year, however, Toliver began to dilute the more acidic aspects of her intensity. As a result, the guard had her best season as a professional and played a vital role in helping the Los Angeles Sparks reach the WNBA playoffs.

Toliver and the Sparks begin the Western Conference playoffs Thursday against the San Antonio Silver Stars. In the Eastern Conference, the Connecticut Sun faces the New York Liberty on Thursday night. The other two first-round series, Atlanta against Indiana in the East and defending champion Minnesota versus Seattle in the West, will start Friday.

The former Terrapin enters the playoffs as the Sparks’ leading scorer (17.5 points per game) and assist generator (4.9 per game) as she averaged 31.5 minutes and made a career-high 33 starts in 34 games. Toliver also established a personal best in field-goal shooting (49.1 percent).

“She’s meant everything to this team,” Sparks first-year Coach Carol Ross said. “Of course, she brings a lot of punch on the offensive end. But she’s also grown her game a lot. She’s much more tuned in to the defensive end. She’s also a heck of a passer, and that sometimes gets overlooked.

“She wants to be a great player. To be really great, you’ve got to come at the game from a place of no fear.”

Until this season, Toliver never made more than 17 starts nor averaged more than 11.2 points or 23.6 minutes.

“This year,” Toliver said, “is the first year where it’s been a breath of fresh air for me.”

Meticulous diligence has defined Toliver since she joined the Chicago Sky as the third pick in the 2009 WNBA draft. Toliver attributes her success to “the daily grind of just working hard, trying to out-work people, not being satisfied with where I am and knowing where I want to be,” she said.

Toliver maintained that approach when the Sparks traded for her in 2010. Yet the grind was pulverizing her.

“She’d be so hard on herself,” Sparks forward DeLisha Milton-Jones said. “She wants to do so well, so badly, that she would dig a deep hole for herself. It was even hard for us as her teammates to help pull her out of it.

“It almost seemed like she was fighting the good we were trying to do for her. She was just so angry and couldn’t get past that last mistake that was made — which, in turn, compounded to two, three, four, five mistakes in a row.”

Toliver’s transformation began during the winter, when she played in Russia for Dynamo Moscow with Mystics forward Crystal Langhorne, a former Maryland teammate.

“It was fun playing with her again,” Toliver said. “We always challenged each other in practice every day. I just got back to my roots playing with her, just having fun again.”

When Toliver returned to the Sparks, she found a coach in Ross who recognized her need for emotional balance.

“She’s been a huge influence on me this year,” Toliver said. “She always said, ‘Don’t give anyone else your power. Don’t let anybody take your power away.’

“When I would get upset or be too hard on myself, I’m giving my power to somebody else, whether it’s a person or just the environment. I’m not owning it. You’ve got to play with joy. That’s what Coach always says.”

Reinforcing Toliver’s budding sense of perspective is former Mystics guard Alana Beard, who joined the Sparks after missing two full seasons because of injuries.

“She’s very positive,” Toliver said. “She also has a new outlook and she shared that with all of us. When you can look at somebody who’s living proof, that’s contagious.”

Toliver’s new resilience passed a major test early. In the Sparks’ fifth game of the season on May 29, she made the winning shot with 1.1 seconds left after committing a WNBA-record 14 turnovers in a 76-75 victory over Tulsa.

“You’ve got to forget about the bad, overcome and still want those big moments,” Toliver said. “I know I’m going to make mistakes. Nobody can play perfectly. That, right there, just takes pressure off of yourself.”

Less self-imposed pressure means greater appreciation for the moment.

“We get to do what everybody else wants to do,” Toliver said about playing. “Coach [Ross] harps on that a lot. I’ve just been trying to enjoy every day and work hard every day because this game doesn’t last forever, as a player.”

Toliver’s struggle between perfection and perspective emerges when she is asked if it hampered her career.

“Absolutely,” Toliver said. “I wish . . . but that’s what life’s about. I’ve grown significantly. I’ve dealt with those battles for a reason. It’s brought me here.”