We've been unabashedly obsessing over Justin Bieber's updated cover of Edwin McCain's 'I'll Be' all day. And in the middle of listening to it on repeat for the thousandth time, we remembered that Austin Mahone also covered the track in his pre-fame days -- and recently! Whose version of the romantic song is your fave?

As anyone who has watched Justin Bieber's KidRauhl versions of the song would know, there's a reason that the kid was discovered on YouTube -- and 'I'll Be' is one big one. The Biebs shows off his skills on that acoustic guitar like there is no tomorrow, while also pouring the kind of emotion into the vocals that is way beyond his young age. Years later, Bieber proved that he's still got it, undoubtedly getting the audience weak in the knees while he belted out the cover during a recent acoustic set. Beliebers, you can check out a compilation vid of the Biebs' covers of 'I'll Be' through the years below.

Like Justin Bieber, Austin Mahone also covered the Edwin McCain track as a young teen, accompanying himself on the acoustic guitar, braces and all. (You can watch 14-year-old Austin Mahone belt it out here.) While we're totally digging the nostalgic vibes, we love his updated cover of the song even more -- it's a little more polished and a little more mature, and even more swoon-worthy than ever. Check it out in the video below!

Whose cover of 'I'll Be' do you like better? Cast your vote for Justin Bieber or Austin Mahone in the poll below!

Watch Justin Bieber Cover 'I'll Be' Throughout the Years

Watch Austin Mahone Cover 'I'll Be'

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