BERLIN, April 14 (Xinhua) -- Borussia Dortmund captain Sebastian Kehl scored to help his team beat Schalke 2-1 in the 140th Ruhr derby and continue its march to the Bundesliga title on Saturday.

With the victory Dortmund set a new Bundesliga record of 25 games unbeaten as the defending champions built up a comfortable eight points lead over second placed Bayern Munich, which were held to a 0-0 draw by Mainz in the late game.

Jefferson Farfan had given Schalke the lead in the ninth minute, but Lukasz Piszczek equalized from a narrow angle nine minutes later and Kehl scored after a corner.

Elsewhere, Kaiserslautern are almost certainly relegated after losing 2-0 to Nuremberg, Bayer Leverkusen drew 3-3 with Hertha Berlin, Augsburg won 2-1 at Wolfsburg, and Hamburger SV claimed a 1-0 win over Hannover.