March Madness 2017 is a month-long competition on PopCrush to determine the best of the best of South Korean boy bands and girl groups.

This round is now over! Vote for f(x) in the semi-finals here!

The battle begins today between f(x) and Red Velvet — two troupes with fiercely loyal fanbases and very different sounds — now going head-to-head in the first round of PopCrush's 2017 March Madness series.

Electro-troupe f(x) made their big debut all the way back in 2009, supplying four full-length studio albums ever since 2011's Pinocchio. After releasing "4 Walls / Cowboy" in Japan last year, the girls are expected to return with a South Korean comeback later this year.

Red Velvet, on the other hand, debuted in 2014 with their alternating concepts between cutesy, sugar-coated pop and smooth R&B. Their latest mini-album, Rookie, debuted in February of this year and the girls remain steadily focused in promo mode.

The battle starts now: place your vote between f(x) and Red Velvet. This round ends on March 10.

Join the conversation on social media! Use #PCMarchMadness to discuss this year's competition.

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