Blake Shelton had to send teen twosome Xenia and Sara Oromchi into battle for this week's 'The Voice.' It was the last of the battle rounds before the live shows and Shelton chose The Pretenders' big, room-filling ballad, 'I'll Stand by You' for the shy girls -- since these two ladies are a little low key and still in their shells, despite being incredibly talented.

From the get-go, Shelton noted that both ladies are a bit bashful and he recognized that it was do-or-die time as the two went voice-to-voice. He wanted to see which songbird could stand out in this duet. Shelton knows he has one last chance to assemble to strongest team out there, and he certainly allowed his advisor Reba to dispense her typically sage-like advice to the teens, advice which they can take with them whether or not they advance. Additionally, the teens were wise to ask the confident singers how to bring attitude to their performances; that's called using your resources, kids!

"I want you to scare me because you are singing confidently" was Shelton's most honest piece of advice to Xenia and Sara.

The battle round was quietly beautiful and a bit flawed, as each singer has a pretty voice. Xenia certainly has a unique, rare tone and Oromchi was a bit pitchy. It's a difficult song -- which Pia Toscano nailed on 'American Idol'-- and Shelton said that the music business is just that and only the strong survive.

Xenia ultimately took the round and she is the last addition to Team Shelton, which is also populated by Patrick Thomas, Jared Blake and Dia Frampton.

Blake Shelton Fans: We’re giving away another autographed copy of Blake Shelton’s new single, ‘Honey Bee’! After you’ve left your comments with your thoughts on this week’s ‘The Voice’ below, enter to win the signed CD by following @tasteofcountry on Twitter and re-tweeting the announcement of the giveaway. You must enter by 11:59PM ET on Wednesday, June 1. We’ll choose one winner at random. Good luck!

Watch Xenia and Sara Oromchi Perform 'I'll Stand by You' on 'The Voice