of 2006 and signed a four-year contract until 30 June 2010, with Leverkusen paying €6.5 million for his signature. On 12 August 2006, Kießling made his first appearance for the new club, coming on as a substitute. After arriving in Leverkusen, he netted eight goals in the 2006–07 season, 16 goals in the 2007–08 season, and 14 goals in the 2008–09 season. On 5 April 2009, he scored his side's first goal in a 2–0 win over 1. FC Köln, keeping alive Leverkusen's chances of qualifying for Europe for the following season. Leverkusen trailed off following the win, eventually falling to ninth place in the final Bundesliga standings. In August 2009, he was voted as Bundesliga Player of the Month. He then scored a hat-trick for Bayer Leverkusen against Stuttgart on 29 November 2009, sending the club to the top of league table with a 4–0 win, three points clear of closest challengers Werder Bremen. On 16 March 2010, Kießling signed a contract extension with Leverkusen, tying him to the BayArena side until 2015. He continued his impressive form in the 2009–10 season, scoring 21 goals in 33 games and finishing the season as the second highest goal scorer in the Bundesliga after Edin Džeko, with 22. He was also included in the Bundesliga Team of the Season. Kießling finished the 2010–11 season with nine goal in 29 matches. On 18 February 2012, Kießling scored two goals on only three shots and also provided an assist for André Schürrle as Leverkusen defeated FC Augsburg 4–1. On 5 May, he scored a hat-trick on the final day of the Bundesliga season, helping his side to a 4–1 win over former club Nürnberg and securing fifth place in the final league standings. Kießling finished the 2011–12 season with 17 goals in 43 matches. 2012–13 season His first goal of the season came in Leverkusen's opening match of the Bundesliga campaign on 25 August 2012, netting the opener as his side fell to a 2–1 defeat to Eintracht Frankfurt. Kießling scored his only goal of Leverkusen's Europa League campaign on 4 October, coming on as a substitute and scoring the winning goal away to Norwegian side Rosenborg BK. On 15 December, Kießling scored a brace to keep Bayer close on the heels of Bayern Munich heading into the winter break; the goals also meant that at mid-season he was the top scorer in