Taylor Swift still has it! Not only did she sellout 4 nights at L.A.’s Staples Center, but celebrities graced the stage and  surprised the audience. 

Surprise guests included Justin Bieber and Jason Mraz, who each joined her for  duets. Sunday night she had another surprise for her fans. Ellen DeGeneres!

“I was looking for the ladies room. I am so sorry,” quipped DeGeneres after appearing onstage.

“This has been happening quite a bit,” Swift joked. “People are just going about their daily lives and they end up on our stage. It happened a lot this week.”

DeGeneres then sat in and help with ‘Our Song’.  She  shared the news on Twitter: “Just got off the stage with @TaylorSwift13 at Staples Center. Our song is now ‘Our Song.’”

[via PopCrush]