Robert Lewandowski was expected to sign with Bayern this summer but waited until this week sign a contract.

DORTMUND, Germany (AP) - Poland striker Robert Lewandowski says he will give his all for Borussia Dortmund before switching to Bundesliga rival Bayern Munich at the end of the season.

Lewandowski, who signed a five-year deal with Bayern on Saturday, told Dortmund fans on the club website: ''We still have half a year ahead of us in which we have certain targets that we want to achieve together. Even if there are a few fans among you that don't agree with my decision, I hope for your support!''

The 25-year-old adds: ''In any case, I will give everything for Borussia Dortmund! Your Robert Lewandowski.''

Lewandowski, who joined Dortmund in 2010, was free to join Bayern at the end of the season after declining to extend his existing contract.

Copyright 2014 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

SI Apps
We've Got Apps Too
Get expert analysis, unrivaled access, and the award-winning storytelling only SI can provide - from Peter King, Tom Verducci, Lee Jenkins, Seth Davis, and more - delivered straight to you, along with up-to-the-minute news and live scores.