The Petaluma and Casa Grande high school cross country teams begin serious pursuit of the state’s top prize Wednesday in the Sonoma County League championship run at Spring Lake in Santa Rosa.

Petaluma’s boys, ranked No. 1 in the state among Division III schools, and Casa Grande’s talented girls will be favorites for not only league titles, but even bigger honors in post-season races.

Competition ran true to form last week, when the local teams ran head-to-head on Petaluma’s home course at Helen Putnam Park.

Petaluma’s boys dominated, sending home seven of the first eight runners in a 15-48 win over their rivals. Petaluma’s Sterling Lockert bettered his own course record, lowering his standard to 17:07.

He was followed by Brandon Felipe in 17:34, Devin Lockert in 17:47, Hugh Dowdy in 17:52 and Forrest Shaffer in 17:52.

Casa Grande’s first finisher was Spencer Hall, who ran sixth in 18:09, recording the second best time ever by a Gaucho runner on the Petaluma course.

Casa Grande had too much depth for the Lady Gauchos, prevailing, 26-31. Casa’s Jacque Taylor was also a record breaker, lowering her own course record to 19:40.

Petaluma’s Isabell Andrade bested the old record, finishing in 20:49, the second fastest time on the course.

Petaluma’s Francessa Honey was third in 21:33, followed by Casa Grande’s Dominique Ratto, fourth in 21:43, and Petaluma’s Kelly Lucchesi, fifth in 22:42.

Casa Grande won, with Eva Luu finishing sixth in 22:50, Kylie Buck sixth in 23:33 and Taylor Falk seventh in 23:54.

Petaluma’s junior varsity boys won, 17-42. Clark Bernard in 19:02, Roberto Gonzalez in 19:07 and Seth Yungert in 20:11, gave Petaluma the first three places, with Troy Gaub, fifth in 20:39, and Ben Neslon, sixth in 20:58, completing the counting Trojans.

Tyler Harwood broke up the Petaluma domination, finishing fourth in 20:34.