Yes, there was indeed a teaser for Rocky 4. I have it on VHS tape somewhere, but have over 2000 tapes and am in the process of moving so it would take forever for me to find it.

However, I watched it about a million times back in 1985 and have memorized it completely. The dialogue is as follows:

"My name is Drago. I am fighter from Soviet Union. I fight all my life, and I never lose. Soon I fight Rocky Balboa and the whole world will see his defeat. Soon the whole world will know my name."

Then you see Rocky taping his fists, training and then both of them dancing around the ring in slo-mo. They then launch punches at each other, and it cuts to two boxing gloves meeting and exploding, followed by the words "Rocky IV" and a voice saying "get ready for the next world war."

If I ever find it again, I will try to transfer it to a digital file and send it to you.

DocP