Bayer Leverkusen took another step towards a first Bundesliga title on Sunday when they won 2-0 at 10-man Cologne to go 10 points clear at the top of the table and stretch their unbeaten run all season to 34 matches. Cologne’s Jan Thielmann was sent off 14 minutes into the regional derby for a reckless challenge against Granit Xhaka, and Jeremie Frimpong opened the scoring in the 37th. Leverkusen were lucky when Cologne’s Sargis Adamjan was denied by the post before Alejandro Grimaldo wrapped up their 30th victory in the unbeaten run in the 73rd. Xabi Alonso’s Leverkusen increased their league…