Luke Littler has been joined in New York by his female friend Faith Millar as he prepares for the US Darts Masters.
The 18-year-old darts sensation could be spotted cosying up to his friend in an Instagram post ahead of the tournament kicking off at Madison Square Gardens on Friday.
The picture, posted by Millar and later shared by Littler, shows the pair close together, with the 19-year-old wrapping her arm around the darts star, who is wearing sunglasses and a blue top.
Millar accompanying Littler abroad represents a next step in their relationship, with the beauty specialist already having attended a number of the world No 2's events.
They were seen leaving the Utilita Arena together in Newcastle after the Nuke won the eighth night of the Premier League and she was also at a Q&A session organised by his darts sponsors BoohooMan in Manchester in March.
Littler is enduring a challenging period at the oche, falling to a disappointing defeat in the Premier League final last month when he lost against rival Luke Humphries before crashing out of the World Cup in the first round.
Littler was spotted cosying up to his 'female friend' ahead of the US Darts Masters in New York
The darts star went public with his 'friendship' with beautician Faith Millar earlier this year
Luke Littler has now taken the next step in his friendship with his fun-loving Faith Millar
He then partnered World No 1 Humphries at the competition in Frankfurt, but was targeted by the crowd from the first dart and suffered a shock defeat against home favourites Germany.
But the 19-year-old is enjoying life outside of darts, having signed a brand deal with McDonald's and appearing on Gogglebox.
The US trip comes just a week after he was seen in Spain celebrating his mother's birthday with Millar.
He shared another snap featuring his female friend, as well as eight other people as they appeared to celebrate Lisa Littler's birthday in Spain.
Littler shared the post on social media, captioning it: 'Happy birthday mum,' with a love heart emoji, Spanish flag emoji and a sunglasses emoji.
Meanwhile, in May, Littler swapped his darts for drinks as he hit the town with Millar and pals, sharing a picture of the group at a table full of beverages in a pink-lit booth in a mystery location, his arm draped around her.
She was also seen cheering him on at the O2 Arena at the end of last month as he missed out on a stunning £275,000 prize pot in the Premier League final.
Mail Sport revealed that Littler met Faith in February and that the pair were understood to have become almost inseparable since.
The 19-year-old beautician was spotted cheering Littler on at the O2 Arena last month
It comes after a rocky time at the oche after England's shock World Cup defeat in Germany
Faith Millar has already accompanied the PDC World Champion to public events this year
However, both have been keen to play down the significance of their friendship - insisting emphatically that they are not dating or in a relationship.
Millar comes from Wigan, just 15 miles from Luke's home in Warrington, Cheshire.
Eyelash beauty specialist Millar is also believed to have met Littler's parents while visiting the 18-year-old at his mansion.
A source told MailOnline: 'Faith and Luke have become firm friends and enjoy one another's company a lot.
The blossoming friendship comes nine months after the world number two split from his previous girlfriend 22-year-old Eloise Milburn last June.
At 19, Millar is closer to Luke's own age than Milburn, who was in her twenties when she began dating him while he was just 17.
They split before last year's World Championship, though, and Littler has not said he has had a relationship since.