Bayer Leverkusen have failed to break down Zenit St Petersburg's defence before half time in their Champions League clash in Germany, but have had plenty of opportunities to score in an eventful 45 minutes.
The Bundesliga club started well with Lars Bender firing an early effort wide before Son Heung-Min played in Wendell, whose effort was saved by Yuri Lodygin.
On six minutes, Emir Spahic then met Hakan Calhanoglu's corner and his header was only inches away from giving Bayer the lead after a fearsome start from the hosts.
Son, who proved to be a thorn in Benfica's side when the German outfit won last time out, was causing problems for the Zenit back-line and slipped a through-ball to Karim Bellarabi, but the forward's effort failed to trouble Lodygin.
Zenit's only chances of note in the opening quarter fell to Domenico Criscito and Hulk, but both players saw their strikes blocked by the Bayer backline, who otherwise had little to do.
The Russian side were on the back foot late in the half as Son created chances for Giulio Donati and Calhanoglu, which were both squandered.
Calhanoglu then latched on to the Bender's pinpoint cross minutes before half time and hit the target with his header, but couldn't beat Lodygin.