ZZ Top's 'La Grange' will battle Lynyrd Skynyrd's 'Sweet Home Alabama' in round two of Ultimate Classic Rock's March Riff Madness, with your votes determining the winner.

32 of classic rock’s most iconic riffs were cut down to a field of 16 by your votes last week. We'll repeat this process four more times over the next month until we theoretically arrive at the most awesome riff in all of rock history.

ZZ Top, the pride of Texas, advanced to this round by defeating Boston's 'More Than a Feeling' during round one of this riff against riff battle. Meanwhile, Lynyrd Skynyrd dispatched the Motor City Madman himself, Ted Nugent, by scoring nearly twice as many votes for 'Sweet Home Alabama' than he did for 'Stranglehold.'

So who will advance this time? It's your choice. You can vote once per hour until round two of March Riff Madness closes on Sunday, March 16 at 11:59PM ET. The ultimate March Riff Madness winner will be revealed on Tuesday, April 7.

Watch ZZ Top Perform 'La Grange'

Watch Lynyrd Skynyrd Perform 'Sweet Home Alabama'