When i try to DL and watch a Warcraft 3 ROC replay from the internet it says i need the expansion.?

I dont want to buy the expansion as i stupidly just bought the ROC but where can i view replays with just this game and not the expansion to it?When i try to DL and watch a Warcraft 3 ROC replay from the internet it says i need the expansion.?
The only way is to have the expansion installed, and be on the same patch the replay was played in, there is no way around it.