Welcome to your final four. We started with 32 of the biggest hard rock hits of the 21st Century, opened up the voting to you, the Loudwire Readers, and now we've reached the Semifinals of our Rocktober Rumble tournament.

On one side of the bracket you have the mighty Green Day and their mega-hit "Boulevard of Broken Dreams" squaring off against Linkin Park's instantly memorable earworm "In the End" from their hugely successful Hybrid Theory album. The other side of the bracket found Three Days Grace's low-end gem "Animal I Have Become" rocking up against Avenged Sevenfold's in-your-face anthrem "Nightmare."

Who will advance to the finals? That's up to you. Voting in the Semifinal Round of the Rocktober Rumble tournament runs through Friday, Oct. 28 and fans can vote once per hour through the deadline of 10AM ET. So click the button below to start voting in these semifinal matchups.