I recorded the show and just watched it waiting for GPN's Leno appearance.  
Ashley's voice just isn't powerful enough for that song, but I'll still give a 17yo credit for having the guts to take on a song like Paris and really go for it on the stage knowing full well she'd be compared to Grace.  

For those who aren't familiar with The Voice ... the premise is the contestants aren't 'ready for prime time' and the coaches choose the singers they feel they can do the most with to help them develop their skills.

Christina said this about saving Ashely over the other 2 up for elimination.
" She’s really coming into her own and I just had to keep her around because I want to see where else that goes with her.” 
rest here  http://www.wetpaint.com/the-voice/articles/the-voices-christina-aguilera-on-saving-ashley-de-la-rosa-i-had-to-go-with-my-gut