I know there are quite a few threads already regarding Postfix not receiving external emails. However, my problem is for Gmail exclusively. Postfix on my server receives email from many providers such as Yahoo, Fastmail, etc. just fine. It even receives corporate email hosted on google mail server with Google Apps for Business. Only emails from @gmail.com address don't get through. I don't recall blacklisting or blocking gmail and I can send emails from my server to @gmail.com address perfectly.
I don't know where to start troubleshooting in this case. Please help!