Taylor Swift is mixing things up for her first night at Wembley Stadium ...

inviting frequent collaborator Ed Sheeran onstage for a mega mashup. The pop star brought out the British singer in London Thursday evening for the popular acoustic set she's been doing during the "Eras" tour. It frequently includes songs she rarely performs and fans got an extra special treat this time.

Ed x Taylor - Thinking Out Loud đź“ą gleisa.opaloski pic.twitter.

com/xmrnTbLmth Taylor and Ed proved to be quite "The A Team," as the BFFs sang a mash-up of "Everything Has Changed," "End Game" and "Thinking Out Loud" for surprised Swifties. TS has performed more than 100 "Eras" tour shows, and sometimes special guests join her onstage ..

. including Hayley Williams , Ice Spice , Phoebe Bridgers , Sabrina Carpenter , Gracie Abrams , Jack Antonoff , Aaron Dessner and HAIM . 🎥 | Taylor Swift’s speech about Ed Sheeran tonight ( #LondonTSTheErasTour ) “He’s a second brother of mine.

” pic.twitter.com/7lPbmkYjMV Taylor referred to Ed as her "second brother" while introducing him to the crowd .

.. putting an emphasis on their special bond.

She added ...

"He works so hard and he's on tour right now and he's probably so tired, but he wanted to come and play for you and do this for all of us. So, give it up again for Ed Sheeran." 📹 | Taylor and Ed Sheeran perform a mashup of “Everything Has Changed", "End Game" and "Thinking Out Loud" as a surprise song! #LondonTSTheErasTour pic.

twitter.com/WGwjY7.