She's got some front! Beyonce takes the plunge in VERY low-cut dress as she watches boxing match with husband Jay Z

There's little doubt it was the hottest show in town.   

But Beyonce threatened to steal the show once again when she watched the Miguel Cotto and Saul 'Canelo' Alvarez boxing match with her husband Jay Z, 45, at the Mandalay Bay Events Center in Las Vegas on Saturday night.

The 34-year-old flashed some serious cleavage in an extra low-cut and slinky black gown that did very little to hide her skin. 

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Fight for attention! Beyonce exposed some serious cleavage when she attended the Miguel Cotto vs. Saul 'Canelo' Alvarez boxing match with her husband Jay Z at the Mandalay Bay Events Center in Las Vegas on Saturday

Fight for attention! Beyonce exposed some serious cleavage when she attended the Miguel Cotto vs. Saul 'Canelo' Alvarez boxing match with her husband Jay Z at the Mandalay Bay Events Center in Las Vegas on Saturday

Beyonce's flowing black dress hung delicately over her chest and atop her shoulders, while flashing her leg with a long and sexy slit that began at the waistline.

She wore her light blonde tresses down in full and beachy waves with a centre part, and she brought out her natural beauty with a swipe of deep, smoky eye shadow and a shimmering coat of golden blush.

The Crazy In Love hitmaker upped the sparkle factor with a pair of elegant silver chandelier earrings that had a bright green jewel in the centre, adding a vintage vibe to her glamorous frock.

See more of the latest news, pictures and video updates on Beyonce and Jay Z 

Eyes up here! The Single Ladies hitmaker without a doubt turned heads with her low-cut number

Eyes up here! The Single Ladies hitmaker without a doubt turned heads with her low-cut number

Take the plunge in Beyonce's silk gown by Michael Costello

She might have been attending a boxing match with hubby Jay Z, but Beyonce didn’t have to fight for the fash pack’s attention in this gorgeous dress.

The stunning singer wowed in her plunging draped black silk dress by Michael Costello which she simply worked with a smoky eye and a metallic box clutch bag, and we’re crazy in love with this evening look for a killer Christmas party effort.

From Costello’s dark and edgy Nirvana collection, Bey’s dress is not up for grabs online, unfortunately, but you can think about emulating her look from the edit below with uncanny alternatives from the likes of Asos to Olcay Gulsen.

We'll be styling ours with platform stiletto heels for a daring yet sophisticated finish.

* PRICES MAY NOT BE AS ADVERTISED
Showing what she's got! The Drunk In Love singer is getting ready to face off against Magic Mike XXL star Channing Tatum on the hit Spike TV show, Lip Sync Battle

Showing what she's got! The Drunk In Love singer is getting ready to face off against Magic Mike XXL star Channing Tatum on the hit Spike TV show, Lip Sync Battle

Come on! Jay Z was glued to the match as he applauded in support

Come on! Jay Z was glued to the match as he applauded in support

Vying for attention: Miguel Cotto and Saul 'Canelo' Alvarez duked it out to the entertainment of the superstars in attendance

Vying for attention: Miguel Cotto and Saul 'Canelo' Alvarez duked it out to the entertainment of the superstars in attendance

Combined with her sharply dressed husband, who sported a black suit and bow tie, the couple made for a fashionable twosome. 

Once the fight commenced, the pair seemed to have a hard time taking their eyes off the ring. 

Jay Z's attention was glued to the match, which saw Saul reign victorious in an unanimous decision, as he applauded in support.

Just look at her! The rapper turned his gaze towards his smiling and gorgeous wife

Just look at her! The rapper turned his gaze towards his smiling and gorgeous wife

Riveted: The couple appeared captivated by the atmosphere of the fight

Riveted: The couple appeared captivated by the atmosphere of the fight

The rapper at one point gazed in the direction of his gorgeous wife, who was grinning widely from ear-to-ear.  

No doubt Jay will be watching closely once again when his wife faces off against a former stripper turned Hollywood hunk known for playing a male exotic dancer on Lip Sync Battle

The Drunk In Love singer will be competing against Magic Mike XXL star Channing Tatum on the hit Spike TV show, according to Entertainment Weekly.

The exact air date has yet to be announced but it will surely draw in viewers to the show which has made a name for itself by having famous celebs showdown onstage.

Previous battles have included an epic war between Anne Hathaway and Emily Blunt. 

Reunited! The hitmaker grinned widely as she wrapped an arm around her former Destiny's Child bandmate, Kelly Rowland 

Reunited! The hitmaker grinned widely as she wrapped an arm around her former Destiny's Child bandmate, Kelly Rowland 

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