Munich - Having spent year after year cowering in the shadows of FC Bayern München and Borussia Dortmund, Bayer 04 Leverkusen have at long last emerged as Bundesliga title contenders in their own right.

Second in the standings at the halfway point of the 2013/14 campaign, Sami Hyypiä’s charges could hardly have asked for much more from a hugely ímpressive Hinrunde.

Trailing defending champions Bayern by just a point, die Werkself were going great guns until they travelled to rock-bottom Eintracht Braunschweig on Matchday 11. A surprise 1-0 loss handed the initiative to the league leaders, who now have a seven-point hold and a game in hand on their nearest challengers after Leverkusen - also through to the last 16 of the UEFA Champions League - stumbled yet again against Eintracht Frankfurt and SV Werder Bremen.

Goalkeeper Bernd Leno recorded five clean sheets and conceded just 16 goals between August and December, with only FC Bayern shipping fewer (eight) than Leverkusen in the league so far this season. The 21-year-old has been the model of consistency at home and abroad, delivering one of the finest individual goalkeeping displays to date as Bayer held Bayern to a 1-1 draw back on Matchday 8.

After seven games in the capital, last season’s Bundesliga top scorer Stefan Kießling finally found the back of the net at Hertha Berlin's Olympiastadion on Matchday 13, handing Leverkusen their tenth win from their first 13 games. The last time that happened was in 2001/02 when Leverkusen finished second, just a point behind title winners Borussia Dortmund.

With 70 minutes on the clock in Leverkusen’s trip to 1899 Hoffenheim and the visitors leading 1-0, Kießling headed a Gonzalo Castro cross through a hole in the side netting and into Koen Casteels' goal. Referee Felix Brych let it stand and Bayer went on to win the game. “At first I thought the ball wasn't going to go in, but then there it was, in the back of the net,” said the Leverkusen striker of what would later be labelled the 'phantom goal'.

Heung Min Son will be key to Hyypiä’s bid to repeat the feat of decorated Bundesliga coach Jupp Heynckes, who led Bayer to a runners-up spot in 2011. The South Korean international has exploded onto the scene at the BayArena this term, filling the void left by the departed Andre Schürrle by scoring seven goals - including the winner in Dortmund’s backyard on Matchday 15 - in 14 Bundesliga appearances so far for his new club.