The actress, 34, was seen in several clips on social media singing along to some of her close friend's biggest hits, and in a new interview, she revealed just how close they really are.
Speaking with Vanity Fair at the 2023 Veuve Clicquot Polo Classic in New York, which took place this past Saturday, the 34-year-old described being at the show's opening night.
"The concert was pretty amazing," she gushed. "I was lucky 'cause we've been friends for a really long time.
"I've known her since we were 17 and 18, so she hooked me up, which was very nice 'cause I know those tickets are impossible to get," she confessed.
Emma continued to praise Taylor, 33, for her ability as a performer, which has been put on full display throughout her tour, which recently added a slew of international dates as well.
Her Latin American leg will kick off on August 24 in Mexico and conclude in Brazil on November 26, before which she will release the Taylor's Version of her 2010 album Speak Now.
"She's a wonderful friend. She blows my mind. I mean, the amount of sheer stamina to do three and a half hours and perform 44 songs and to maintain the extreme energy of the audience – I've never seen anything like it."
Emma was asked then if she'd ever consider performing alongside Taylor, having won her Oscar for displaying her chops as a performer in 2016's La La Land.
But she quickly shut that idea down, saying: "Oh, God, hell no! I can't sing for a massive stadium. Let's not even go down that road. She has insane talent – I could never do what she does."
Days after after Emma's comments, reports emerged which claimed that Taylor's whirlwind romance with The 1975 frontman Matty Healy had come to an end, although the reasons for the break-up remain unclear.
The entertainer has been continuing her run of shows for Eras, on a small break before resuming her stage run on June 9 in Detroit.
During a tour stop in Foxborough, MA in May, Taylor shared some personal insights with her fans after her and Matty's reported relationship took steam once they were spotted together. "I've never been this fulfilled in my life, in all its facets, ever," she told the audience.
After performing "Question…?" as the night's surprise song, Taylor confessed the secrets to her happiness and the singer admitted she wasn't just talking about the tour.
She thanked her fans for being a part of her happiness, expressing that the tour felt more like a celebration of a life that finally made sense to her.
Emma, on the other hand, has been maintaining a quieter public profile as a mother to her two-year-old daughter Louise Jean with husband Dave McCary.
She will, however, be kicking off a promotional tour later this year as she prepares for the release of Poor Things in September, which sees her team up once again with The Favourite director Yorgos Lanthimos.
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