Zach Thornton shut out the Seattle Sounders for ...

Zach Thornton shut out the Seattle Sounders for the third straight time, helping Chivas USA to a scoreless tie Saturday.

Thornton earned his 10th shutout to snap a tie with Houston’s Pat Onstad for the MLS lead.

Both teams earned a point to keep them in the playoff mix. Seattle is 9-6-11 with 38 points, and Chivas stayed one point behind at 11-9-4.

Thornton beat the Sounders 2-0 and 1-0 earlier this season, and had to work for his third clean sheet.

In the 15th minute, he got his hand on a shot by Sebastien Le Toux from the top of the six-yard box to deflect it wide of the far post. About five minutes after halftime, a header from the top of the six-yard box by Steve Zakauani was on its way in until Thornton slapped it away.

Then in the 83rd minute, Fredy Montero had a one-on-one try against Thornton from the top left corner of the six-yard box and Thornton came out and blocked the shot. Finally, he denied Nate Jaqua in front of the net during second-half stoppage time.

Thornton finished with six saves in 14 shots by Seattle.

Kasey Keller had his ninth shutout of the season for the Sounders, who went scoreless at home for the fourth straight game.