Bayer Leverkusen have sold Andre Schurrle to Chelsea for £17 million.

Leverkusen have agreed to a straight cash deal after signing Hamburg's Korean striker Heung-Min Son to replace Schurrle.

The 22-year-old will become the first signing of Jose Mourinho's second spell as Chelsea boss, even though he was first identified by Andre Villas-Boas and negotiations have been going on since last summer.

Leverkusen chairman Wolfgang Holzhauser said: "We have made it clear from the beginning Schurrle's departure would only be possible if we found an adequate alternative.

"We have now found this and so there is nothing to stand in the way of Schurrle's move."