Pretty Women: Julia Roberts joins Taylor Swift's squad

SANTA CLARA, CA - AUGUST 15: (L-R) Actress Julia Roberts, Taylor Swift and musician Joan Baez appear together during Swift's "The 1989 World Tour" at Levi's Stadium on August 15, 2015 in Sa

She may count some of the world's most famous women among her friends.

But even Taylor Swift admitted she was star struck when she was joined on stage by Julia Roberts and Joan Baez.

The Oscar-winning actress and the folk singer appeared during the California leg of Swift's latest tour, called 1989.

The 25-year-old said she was 'in awe' as the three held hands, describing the two women as her 'heroes'.

Swift has thrilled fans by inviting celebrity guests to accompany her throughout her tour, which is named for the year she was born.

However she looked particularly overjoyed at the presence of Roberts, 47, and Baez, 74 - beaming as they danced to her hit song Style.

The pair weren't the only special guests invited along for the evening. British band Little Mix also joined Swift on stage, performing their hit song Black Magic.

Swift has delighted fans with a variety of special guests throughout the US leg of her tour, including Kiwi singer Lorde, who flew more than 18 hours to join the chart topper on stage.

Last week, veteran actors Sir Ian McKellan and Sir Patrick Stewart also graced Swift's stage, while other guests have included Ciara, Lena Dunham, Kendall Jenner, Gigi Hadid, Uzo Aduba, Nick Jonas, Serena Williams, Cara Delevingne and Mariska Hargitay.

The tour will take swift to Asia in November, before it concludes in Australia in December.

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- Daily Mail and nzherald.co.nz