Taylor Swift had one very special guest join her on stage at Staples Center for the fifth – and last – of her record-breaking sold out shows in Los Angeles on her 1989 World Tour.

Bestie Selena Gomez, 23, sent fans crazy when she appeared with Taylor, 25, in a spectacular performance that was a fitting conclusion to the phenomenally successful five night run.

The duo sang Selena’s single Good For You that Taylor said back in June was her ‘favorite thing she’s ever done’.

Scroll down for video

Wow factor: Taylor Swift brought BFF Selena Gomez on stage to perform a duet of the former High School Musical star’s single Good For You

Girl power: The two best friends sent fans into a frenzy as they stepped out wearing matching black thigh-high boots

The besties wore sexy outfits for their duet and both had on thigh high black heeled boots.

Taylor wore a white cropped top that flashed some cleavage and a pair of white hot pants connected to her boots with suspenders.

Selena opted for a black romper with spaghetti straps and a plunging neckline.

Bringing sexy back: Taylor and Selena wore matching sexy outfits, the Shake It Off singer in white and the former Disney tweener in black as they sang and danced together

Close: In an interview  this past Sunday, Selena had gushed about how Taylor ‘is one of the greatest people’ and how the singer had helped her get over her breakup with first love Nick Jonas

Also joining the Shake It Off star on stage was actress Lisa Kudrow.

In a surprise move, the Friends star sang her sitcom character Phoebe’s composition Smelly Cat with Taylor, which almost brought the house down.

But The Fearless star wasn’t done yet.

Next up was Justin Timberlake.

Rocking it: Taylor changed into a sequinned leotard with cut-out transparent panels for her duet with Justin Timberlake, who wore jeans, jacket and a fedora

Fans gone wild: Justin, who Taylor reminded her fans was her favorite artist, sang his song Mirrors with the Fearless songstress accompanying him

Let me take a selfie: Taylor and Justin larked around snapping selfies backstage

Quirky: In an offbeat twist, Friends star Lisa Kudrow brought along her guitar and she and Taylor performed Smelly Cat, the song composed by Lisa’s character Phoebe on the long-running NBC comedy

Among the celebs in the audience for the final LA concert were Hollywood actress Reese Witherspoon, Victoria’s Secret model Alessandra Ambrosio and Ruby Rose, who grabbed a photo backstage with the singing superstar.

Also there were Julianne Hough and Mario Lopez, with wife Courtney Mazza, who bumped into each other as they arrived separately.

Nina Dobrev tweeted a photo of herself with pals all glittered up and wearing fake tattoos as they excitedly made their way to Staples Center.

Taylor will resume the US leg of her tour in San Diego on Saturday, before a string of dates across the US in September and moving to Canada in October.

She will take her tour overseas to Singapore, Shanghai and Australia later this year, before wrapping it up on December 12 following a total of 85 gigs.

Backstage pass: Ruby Rose, second from left, and her ‘squad,’ pose backstage with Taylor before Wednesday’s night’s concert

Star guest: Dancer and television personality Julianne Hough showed up for Taylor’s final concert wearing a black lacy cropped top with hip-hugging black jeans ripped at the knees and laced heels

Pins on parade: Vampire Diaries actress Nina Dobrev put on a leggy display in denim hotpants, which she teamed with a black vest, plaid shirt and chocolate brown leather boots

Fancy seeing you here: The newly engaged Julianne, 27, shared a laugh with the Extra TV host

Date night: Mario, 41, showed up with his wife of three years Courtney Mazza who, like Julianne, wore ripped jeans and strappy heels which she paired with a black top and black leather jacket