How to extract text from one specific response while in "follow redirect"?

[Nop Lists <no...@gmail.com>]

Hello,
a tricky question this time...Hope anyone can help.
For a specific request which involves many redirection I use the "follow
redirects" flag.
It happens that it redirects 2 times so I get 3 responses.
Now I Must extract some text (a server name) from the FIRST of these
responses.
How can this be done?
My understanding is that the post-processing extractor operates  on the last
(third in this case) of the responses.

Any hint?

Further explanation:
what I test is a process which involves SSO calls.
A workflow is taken place on a first server. That some redirection notifies
the client the address of the next server. This happend in the first of the
3 responses I mentioned above.
Now the next request goes to this second server, which I can NOT know
beforehabd (statically)...

Any help will be appreciated!
Nop