CLAIRE C. LAURENCE/Arizona Daily Wildcat Sophomore outfielder Trevor Crowe slides into second base during a game against UCLA April 10. The Wildcats, set to open a nine-game swing away from Sancet Stadium, will face Washington in a three-game series this weekend in Seattle.

For the Arizona baseball team, this weekend is the biggest of the season to date.

The Wildcats should get used to that; every series from here on out could hold that same label.

Arizona (21-15-1, 5-4 Pacific 10 Conference) starts a stretch of five Pac-10 series in the next six weeks today in Washington - and considering how tight the Pac-10 standings are right now, all of them could play a significant role in the Wildcat effort for a playoff bid.

"Everything you've done up to now hopefully gets you ready to play these next six weekends," head coach Andy Lopez said.

Arizona travels to Seattle for a three-game series with UW this weekend, beginning today at 6:30 p.m. The Wildcats and Huskies conclude the series tomorrow and Sunday with 1 p.m. games.

The Wildcats and Huskies (21-13-1, 5-4) are tied for second place in the conference. The winner of the series could hold sole position of second behind Stanford.

"We just have to play well every weekend. Nothing has changed," Lopez said. "We haven't had an easy weekend since the day we started."

Right now, only one game separates the second-place team from the seventh-place team in the conference. But with Pac-10 play resuming this weekend, matters should clear up in the next few weeks.

"It makes sense," Lopez said. "Stanford seems to be the team that is out there, but they're only a couple games up. Nobody's got a real handle on the conference, and whoever is playing the best that weekend will get it done."

Lopez said his team will have to finish at least fourth in the Pac-10 to earn a regional playoff berth. In the past, the top three teams in the conference were shoe-ins for the postseason, with the fourth team as a question mark. However, with this season's tough nonconference schedule, Lopez thinks the Wildcats will deserve a bid if they finish in the fourth spot.

Junior Koley Kolberg (6-2, 3.38 ERA) will throw against Washington's Kyle Parker today. Parker is one of two freshmen who have worked their way into the Huskies' rotation. He's earned a 3.94 ERA in his first year at UW.

Even more impressive is the work of freshman Tim Lincecum, scheduled to throw against the Wildcats on Sunday against sophomore John Meloan (3-0, 6.23 ERA). Lincecum (4-1, 2.95 ERA) leads the nation in strikeouts per nine innings and is second in the Pac-10 in ERA among starting pitchers with more than 10 starts.

Wildcat sophomore Kevin Guyette (5-4, 5.35 ERA) faces Washington's Matt Kasser (2-0, 6.91 ERA) tomorrow.

Arizona enters the series on a season-high-tying, five-game winning streak. The series against Washington will begin a nine-game, three-series road trip for the Wildcats.

"We build up (on nonconference games) to play in the Pac-10," junior outfielder Jeff Van Houten said. "Every series is important in the Pac-10. You want to win every single series."