[MLS PREDICTION] All the strategies and matchups and tactical nuances for the first leg of the Western Conference semifinal series between Seattle and Houston Thursday at Qwest Field might be tweaked somewhat if the conditions come up wet and windy. Whatever the weather, a seething atmosphere generated by a crowd of 36,000 should make for a memorable spectacle.

THURSDAY
SEATTLE (12-11-7) vs. HOUSTON (13-8-9), 10 p.m. ET, ESPN2/ESPN Deportes
One point apart in the standings and in goal difference during the regular season, this is in every way a tossup between the second- and third-place teams in the Western Conference. Seattle won a regular season meeting and a U.S. Open Cup match by 2-1 scores at home; in Houston, the teams tied, 1-1. Both conceded 29 goals during the regular season and are excellent in the nets, potent up front, secure in midfield, and well-stocked with experience.

The dazzling speed and interplay Seattle has exhibited at times this season on its artificial surface could be accelerated if the field is slippery fast, yet a saturated surface would slow down pacy rookie winger Steve Zakuani, whose runs are hit and miss but always threatening, and livewire forward Fredy Montero. Instead, balls may be played to 6-foot-3 Nate Jaqua to knock down for Montero and Freddie Ljungberg. And watch out for rugged, driving midfielder Brad Evans, who scored the winner against Dallas Saturday with a superb first-time flick, and the serves of left back Leo Gonzalez.

At the other end, mid-summer acquisitions Dominic Oduro and Abe Thompson have injected more pace into the Houston attack; Brian Ching and Cam Weaver offer size and heft. Adding to the intrigue is the sprained knee of Dynamo midfielder Ricardo Clark, whose quickness and range can buttress the center behind Stuart Holden, who hasn't registered a goal or assist in league play for two months, and Brad Davis, co-league leader in assists with 12.

Houston's Geoff Cameron and Bobby Boswell have played strongly in central defense, yet Adrian Hainault has been a very underrated but very consistent performer on the outside. Might the relatively untested left back Mike Chabala get tested, and perhaps toasted, if he plays?
Prediction: Seattle 1, Houston 0.

RIDGE MAHONEY'S 2009 PREDICTION RECORD.
Last weekend: 2-5. Regular season: 104-121 (46.2 percent).