Bayer come back to stay in contention
Bayer Leverkusen fought back from an early deficit to keep their slim chances of the Bundesliga title alive with a 2-1 home victory over Hoffenheim.
Hoffenheim took the lead after 28 minutes thanks to a strong individual effort from Sigurdsson.
Bayer's Kadlec, Renato Augusto and Sami Hyypia all were not determined enough in challenges and the Iceland international found space for a one-on-one against goalkeeper Rene Adler and struck home into the far left corner.
Sigurdsson was close to doubling his tally in the 38th minute but hammered his 27-yard strike off the right post.
However, Bayer equalised two minutes later from a set-piece with Kadlec heading home Vidal's corner from the right. The hosts made it 2-1 just six minutes after the break, taking advantage of some clumsy Hoffenheim defending.
Ryan Babel's attempted clearance bounced off team-mate Sebastian Rudy to Vidal, who watched as Hoffenheim defender Isaac Vorsah stumbled on his high pass to Stefan Kiessling, and the Chilean international ran onto the loose ball and blasted past goalkeeper Tom Starke.
Starke kept his team in the game with two superb saves to deny Kiessling and Hyypia in quick succession. Kiessling was close again with nine minutes left and Hoffenheim could not break down the Bayer defence to grab an equaliser.