Nicole Scherzinger threw a 'booze-fuelled afterparty' with X Factor's Matt Linnen after last weekend's live shows, sources have claimed.

The Pussycat Dolls star, 39, reportedly ended up drinking with the hunky plasterer, 28, until the early hours of Monday morning at the London studios.

The show heartthrob and father-of-three allegedly has a 'huge crush' on Nicole and was 'flirting' with her all night - amid claims he has dumped love interest and fellow contestant Grace Davies.

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Rumour has it: Nicole Scherzinger threw a booze-fuelled afterparty with X Factor's Matt Linnen (far right) after last weekend's live shows, sources have claimed

Sources claimed the Overs mentor threw the party for all her contestants on Sunday night in her dressing room - and ended up getting on famously with Matt.

'Nicole hosted a bit of a party after the show last weekend and she and Matt ended up staying till very late drinking,' a source told The Sun.

'They get on really well and are pretty flirty with each other, though obviously it's all innocent as Nicole is still seeing her boyfriend.

'The next day Matt was really feeling it and could barely manage rehearsals.'

Hmm: The heartthrob and father-of-three allegedly has a huge crush on Nicole and was flirting with her all night - amid claims he has dumped love interest and fellow contestant Grace Davies (pictured)

Firm friends: The Pussycat Dolls star, 39, reportedly ended up drinking with the hunky plasterer, 28, until the early hours of Monday morning at the London studios

Security at the studios were reportedly unimpressed by their late-night partying as they wanted to lock up and head home.

However, a source has disputed the claims to MailOnline and insisted the party wasn't a 'lock in', due to the hopeful's rehearsal schedule.

They claimed: 'Nicole invited all of her contestants to her dressing room after the show on Sunday to say goodbye to Tracey, they were disappointed she was having to leave the show.

'They didn’t have a lock in as they all had to start work early the next morning.'

MailOnline has contacted representatives for The X Factor and Nicole for comment.

Nicole been dating tennis ace Grigor Dimitrov for two years since splitting from Formula One driver Lewis Hamilton.

Close: 'Nicole hosted a bit of a party after the show last weekend and she and Matt ended up staying till very late drinking,' a source told The Sun

Loving life: 'They get on really well and are pretty flirty with each other, though obviously it's all innocent as Nicole is still seeing her boyfriend,' they added

Good friendship: Overs mentor Nicole has struck up a close bond with Matt during the audition process

It comes amid claims Matt's flirty behaviour towards Nicole has fuelled his alleged split from fellow X Factor contestant Grace Davies, 20.

'Grace and Matt had a bit of a thing together, but he ended it and she is devastated,' a source told The Mirror.

'They hooked up in the kitchen on one occasion, and it looked to everyone else as if they were developing feelings for one another, but Matt cooled things off.

'There's a bit of an atmosphere in the house, now. And it doesn't help that Matt is always flirting with his mentor, Nicole Scherzinger.'

Grace brushed over the romance rumours on Thursday, saying she is simply focusing on her singing career.

'Everyone seems to be speculating on it,' she said at the ITV gala. 'I'm just concentrating on getting on with my singing.'

Oops: Security at the studios were reportedly unimpressed by their late-night partying as they wanted to lock up and head home

Party animal: Sources claimed the Overs mentor threw the party for all her contestants on Sunday night in her dressing room - and ended up getting on famously with Matt

Going strong: Nicole been dating tennis ace Grigor Dimitrov for two years since splitting from Formula One driver Lewis Hamilton

It was initially claimed Matt and Grace had struck up a brief romance inside the X Factor mansion.

A source told the Daily Star: 'Matt and Grace aren't dating – it was basically just for fun. They now act as if nothing has happened. This is the sexiest series yet.'

The insider added: 'There are a lot of attractive people in the house so some contestants are bound to be hooking up.

'Contestants are worried that people talking about flings will affect the votes - they're petrified their fans will turn their back on them.'

It comes after Matt revealed he actually has three children, all under the age of 10, whom he has kept very quiet about throughout the audition process.

Over before it begun? It comes amid claims Matt's flirty behaviour towards Nicole has fuelled his alleged split from fellow X Factor contestant Grace Davies, 20

'Devastated': 'Grace and Matt had a bit of a thing together, but he ended it and she is devastated,' a source told The Mirror

He explained his reasons for not bringing his personal life into the process thus far, namely that he wants to keep his eight, six and four-year-old kids out of the public eye.

'I have a supportive family, but my children don't really know about what's going on,' he told MailOnline. 'Although they've had their teachers at school making comments to them about it.'

He elaborated: 'My music isn't to do with my kids, really. I've seen it as a separate thing. I'm in the public eye, not them.'

One time thing? 'They hooked up in the kitchen on one occasion, and it looked to everyone else as if they were developing feelings for one another, but Matt cooled things off,' the source said

Rivalry? The source added: 'There's a bit of an atmosphere in the house, now. And it doesn't help that Matt is always flirting with his mentor, Nicole Scherzinger'

While Matt admitted he's doing The X Factor to make a better life for his family as well as for himself, he also remarked that he doesn't want to 'use' the children as a way to pull on the nation's heartstrings.

'I do worry that people think,' he said.

Matt - who is not in a relationship with any of the children's mothers - spoke about the attention he's been getting thanks to his rugged good looks, having been branded the heartthrob of the competition.

'It's flattering – it's nice,' he said, coyly. 'It's a little hard to take, but if it gets me votes then I'll take that,' he added, jokingly.

Father: It comes after Matt revealed he actually has three children, all under the age of 10, whom he has kept very quiet about throughout the audition process