How to specify required version to downgrade to?

Ульянка Да <[email protected]> Fri, 14 Feb 2014 12:00:14 +0400
Newsgroups gmane.linux.rpm.yum
Message-ID <[email protected]>
Hi,
man tells downgrade "Will try and downgrade a package from the version currently installed to the previously  highest version (or the specified version)."
Please, how to specify the version?

Regards