Not shy! Katharine McPhee and Scorpion co-star boyfriend Elyes Gable are all over each other as celebrities flock to US Open

Katharine McPhee and her boyfriend Elyes Gable couldn't keep their hands off each other at the US Open

The Scorpion stars, who have been dating for at least a year, kissed and cuddled as they took in another day of tennis at the USTA National Tennis Center in Flushing Meadows.

Katharine flashed her toned stomach in a flirty floral crop top as she canoodled with her British boyfriend.

Lovebirds: Scorpion costars Katharine McPhee and Elyse Gabel shared a kiss while attending the US Open tennis in Queens on Monday

Lovebirds: Scorpion costars Katharine McPhee and Elyse Gabel shared a kiss while attending the US Open tennis in Queens on Monday

The American Idol season 5 contestant's beige bra was visible as she leaned in close to her 35-year-old beau.

The pretty 31-year-old brunette pushed her hair back off her face with stylish sunglasses as she placed a hand on Gable's thigh.

Gable, who has also appeared in Game of Thrones and Body of Proof, reciprocated her affections by kissing her on the lips and then planting a tender kiss on her arm. 

Costars: The pair kissed as they attended the Grand Slam event

Costars: The pair kissed as they attended the Grand Slam event

PDA alert: Affectionate Katharine planted a kiss on her British boyfriend's check

PDA alert: Affectionate Katharine planted a kiss on her British boyfriend's check

Sweet: The pair met on the set of their CBS drama Scorpion

Sweet: The pair met on the set of their CBS drama Scorpion

The former Casualty actor looked relaxed in a blue T-shirt and dark purple pants, and held a glass of beer as he took in the action on the court below.

The pair were attending the Stan Wawrinka versus American Donald Young match, but appeared to be somewhat distracted.

The lovebirds have been dating since meeting on the set of their CBS show, which follows a gang of misfit geniuses who unite to prevent cyber terrorism crimes.

Dinner time: Gable shot a loving look at his girlfriend as they snacked on sushi

Dinner time: Gable shot a loving look at his girlfriend as they snacked on sushi

Staying chill: Katharine wore her light brown hair loose over her shoulders

Staying chill: Katharine wore her light brown hair loose over her shoulders

Careful: The actor concentrated on his chopstick skills

Careful: The actor concentrated on his chopstick skills

Katharine famously split from her producer husband Nick Cokas in 2013 after she was photographed making out with Smash director Michael Morris.

Also enjoying at day at the tennis were Orange Is The New Black stars Dascha Polanco, Danielle Brooks and Adrienne C. Moore.

Polanco, 33, showed off her legs in pale blue short shorts and strappy white heels, paired with a sporty matching jacket. 

Tennis fan: Orange Is The New Black actress Dascha Polanco showed off her legs in short shorts as she joined her costars at the US Open

Tennis fan: Orange Is The New Black actress Dascha Polanco showed off her legs in short shorts as she joined her costars at the US Open

Summer style: The actress wore towering white heels as she headed into the match

Summer style: The actress wore towering white heels as she headed into the match

She wore her hair up in a long ponytail, and added large hoop earrings and silver bangles.  

The women seemed to be having a great time as they cheered on Novak Djokovic and Roberta Bautista at the Arthur Ashe Stadium on Monday.

Brooks and Moore dressed casually for the match, wearing Tshirts and jeans.

No wallflowers: Actresses Danielle Brooks and Adrienne C Moore ham it up for the crowd as co-star Dascha Polanco cracks up

No wallflowers: Actresses Danielle Brooks and Adrienne C Moore ham it up for the crowd as co-star Dascha Polanco cracks up

Enthusiastic: Orange Is The New Black stars Danielle Brooks, Dascha Polanco and Adrienne Moore cheer as they watch the Djokovic vs Bautista match on Monday

Enthusiastic: Orange Is The New Black stars Danielle Brooks, Dascha Polanco and Adrienne Moore cheer as they watch the Djokovic vs Bautista match on Monday

Break: The Netflix stars rested during a lull in the tennis

Break: The Netflix stars rested during a lull in the tennis

Close attention: The actresses appeared caught up in the action on center court

Close attention: The actresses appeared caught up in the action on center court

Selfie time: The outgoing stars snapped a photo with an OITNB fan

Selfie time: The outgoing stars snapped a photo with an OITNB fan

Also spotted at the US Open on Monday were Today hosts Hoda Kotb and Kathie Lee Gifford.

The friends and co-hosts laughed and chatted with other spectators.

Gifford, whose football legend husband Frank Gifford died on August 9, appeared to be in high spirits as she joked with friends.

Tennis time: Today Show co-hosts Hoda Kotb and Kathie Lee Gifford also took in the action on day eight of the US Open 

Tennis time: Today Show co-hosts Hoda Kotb and Kathie Lee Gifford also took in the action on day eight of the US Open 

Good times: Kathie Lee appeared in good spirits, no doubt enjoying the fun after the death of her husband Frank Gifford in August

Good times: Kathie Lee appeared in good spirits, no doubt enjoying the fun after the death of her husband Frank Gifford in August

Chatty: The pair entertained fellow spectators at the Arthur Ashe stadium on Monday

Chatty: The pair entertained fellow spectators at the Arthur Ashe stadium on Monday

Summer style: The Today host wore a fitted white dress and oversized sunglasses

Summer style: The Today host wore a fitted white dress and oversized sunglasses

Singer Gladys Knight also attended the tennis, and took time to post for a photo with fans.

The soul legend wore a pearl necklace, black coat and sunglasses as she watched the Wawrinka vs Young match.

She shared her excitement on Twitter, writing 'US OPEN!!! I'm here' and adding a smiley emoticon.

'Wouldn't have missed it for the world. You know I love me some tennis! lol.'

Soul: Motown legend Gladys Knight was also spotted in the crowd

Soul: Motown legend Gladys Knight was also spotted in the crowd

Having fun: The singer and tennis fan shared her excitement on Twitter, writing that she wouldn't have missed the US Open 'for the world'

Having fun: The singer and tennis fan shared her excitement on Twitter, writing that she wouldn't have missed the US Open 'for the world'

Smile: Knight posed for a photo with a fan

Smile: Knight posed for a photo with a fan

Also seen at the US Open on Labor Day were singer Kelly Rolland and her boxer husband Tim Witherspoon, who brought their cute son Titan Jewell. 

The former Destiny's Child singer stayed cool in a big black hat and jean shorts, while ten-month-old Titan wore a bright orange shirt.

Growing boy: Singer Kelly Rolland smiles with son Titan at the US Open

Growing boy: Singer Kelly Rolland smiles with son Titan at the US Open

Tennis lovers: Kelly waved to fans as husband Tim Witherspoon lifted their 10-month-old son

Tennis lovers: Kelly waved to fans as husband Tim Witherspoon lifted their 10-month-old son

Sleepy: Former boxer Tim held tight to tired Titan as the singer looked on

Sleepy: Former boxer Tim held tight to tired Titan as the singer looked on

 Victoria's Secret model Toni Garnn also took in the action in Flushing Meadow.

The German-born beauty, who dated Leonardo DiCaprio for a year before splitting in 2014, wore a stylish blue hat and round sunglasses as she watched the tennis.

She stayed cool in the 90-degree heat thanks to a loose white tank top, which she paired with a gold necklace. 

Stylish: Model Garnn kept the sun off her face with a cute blue hat

Stylish: Model Garnn kept the sun off her face with a cute blue hat

Relaxed: The model flashed a smile as she chatted with a friend

Relaxed: The model flashed a smile as she chatted with a friend

Tennis whites: The model looked lost in thought as she stretched her legs

Tennis whites: The model looked lost in thought as she stretched her legs

Also there to support Andy Murray was his pregnant wife Kim, 27.

She was joined in the box by Northern Ireland TV presenter Christine Bleakley and her footballer fiance Frank Lampard, who plays for The New York City FC.

The mother-to-be wore a white-and-blue striped top and kept cool in the sweltering summer heat with a cute blue fan.

Murray fans: Footballer Frank Lampard, Kim Murray and TV presenter Christine Bleakley watched in Andy Murray's match

Murray fans: Footballer Frank Lampard, Kim Murray and TV presenter Christine Bleakley watched in Andy Murray's match

US Open: Soccer player Frank Lampard chats with finance Christine Bleakley

US Open: Soccer player Frank Lampard chats with finance Christine Bleakley

Staying cool: Kim Murray waved a blue fan as she supported her husband

Staying cool: Kim Murray waved a blue fan as she supported her husband

Also attending the event was Sami Gayle.

The Blue Bloods star kept her cool in a navy blue Polo shirt dress and wore her hair pulled back off her face.

She was in good company as Jesse Metcalfe and his partner Cara Santana were there to watch some tennis as well. 

Jesse was dressed for seemingly much cooler weather in a jumper and shirt ensemble.

Sporty chic: Blue Bloods star Sami Gayle kept her cool in a navy blue Polo shirt dress and wore her hair pulled back off her face

Sporty chic: Blue Bloods star Sami Gayle kept her cool in a navy blue Polo shirt dress and wore her hair pulled back off her face

Autumn look: Meanwhile Cara Santana and Jesse Metcalfe were dressed for cooler climes

Autumn look: Meanwhile Cara Santana and Jesse Metcalfe were dressed for cooler climes

Chatting away: Dylan McDermott and his girlfriend chatted all the way through

Chatting away: Dylan McDermott and his girlfriend chatted all the way through

Bored already: Dylan McDermott was seen yawning in the stands

Bored already: Dylan McDermott was seen yawning in the stands

Also there: Christine Taylor and Ben Stiller were seen in the stands on the eighth day

Also there: Christine Taylor and Ben Stiller were seen in the stands on the eighth day

Close eye: Christine and Ben looked like avid tennis fans

Close eye: Christine and Ben looked like avid tennis fans

Tennis fan: US Vogue editor in chief Anna Wintour was there to watch the tennis on the eighth day

Tennis fan: US Vogue editor in chief Anna Wintour was there to watch the tennis on the eighth day

 

 

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