Taylor Swift 'Red' Tour Surprise, Tegan & Sara [PHOTOS & VIDEOS]: Sister Singers Join '22' Songstress for Special Live 'Closer' Collaboration, Twitter Loves It

Taylor Swift is still on her gigantic arena tour in support of her latest album, "Red," and she has been known to bring out some special guest performers for her concerts. She recently brought out Carly Simon for a duet of "You're So Vain," and also had rapper T.I. and Jim Adkins (Jimmy Eat World) surprise fans in the past. This time around, Taylor brought out the sister duo Tegan and Sara for a special performance of their new song "Closer." Swift was having a ball during the performance and the Canadian sisters have expressed their gratitude for Taylor on Twitter.

Check out this fan footage of the special collaboration right here:

Here are some Twitter reactions (including some from Taylor, Tegan, and Sara) to the "Closer" performance:

So.... @teganandsara just came out and surprised the crowd with 'Closer' and made an entire sold out Staples crowd DANCE. Unreal!!!

— Taylor Swift (@taylorswift13) August 21, 2013

Just got #closerwithtaylorswift onstage at Staples Centre in LA. It's all a blur but I think it was really fun. Photos to follow! #REDLA — Tegan and Sara (@teganandsara) August 21, 2013

“@STAPLESCenter: Tonight's special guest @taylorswift13 sold out night 2/4 was the incredible @teganandsara #RedLA pic.twitter.com/tnEMcTU0WG”

— Tswift ♡ (@HugsForTaylor) August 21, 2013

OMG CLOSER!!!!! #TEGANANDSARA #RedLA  https://t.co/IM9PAlN5BU — T Swizzle (@TT4Taylor) August 21, 2013

@taylorswift13 just brought out guests #TEGANANDSARA! https://t.co/m3tRCOYqxk

— Alex Shiri (@SHEERMONEY) August 21, 2013

Getting air with @TaylorSwift13 and the #REDLA crowd while singing #Closer at Staples Center! https://t.co/b5N2RmXCl2 — Tegan and Sara (@teganandsara) August 21, 2013

Feeling so freaking lucky to have shared the stage with @taylorswift13 to perform #closer We vote Taylor for president. What a #heartthrob

— Tegan and Sara (@teganandsara) August 21, 2013