Grigor Dimitrov praises girlfriend Nicole Scherzinger as he wins ATP Finals in London – despite her missing it for X Factor

NICOLE Scherzinger's tennis champ boyfriend Grigor Dimitrov has opened up about his incredible feelings for the X Factor beauty and said: "She's amazing."

In a rare public show of affection Grigor, who hardly speaks about his relationship with Nicole, 39, praised her after his triumphant ATP Finals win at the O2 in London.

At 26, the Bulgarian is 13 years Nicole's junior, and he had plenty of praise for his missus although she missed the show because of X Factor duties.

Grigor said: "I want to thank one person here, my girlfriend Nicole."

He continued: "She’s somewhere hiding. She deserves quite a bit of credit this week, she’s been amazing."

The tennis star defeated Belgian David Goffin 7-5, 4-6, 6-3 in the captivating final at the O2 Arena.

Grigor became the first debutant to win the championship since Spanish player Àlex Corretja in 1998.

Meanwhile, the former Pussycat Doll was at The X Factor, which saw contestants Rai-Elle Williams and Holly Tandy eliminated during the shock quadruple elimination weekend on Sunday.

She has dated the tennis hunk since her split from racing driver Lewis Hamilton in 2015.

Grigor was linked to newly married Serena Williams in early 2012, and Maria Sharapova later that year, where they enjoyed a two-year romance.

Nicole and her beau are known to keep their relationship under the radar.

Though she is fiercely private about about him, Nicole is also besotted with Grigor.

The couple have been dating since 2015 but she has been typically more tight-lipped on their romance, following her high profile on-off relationship with Lewis.

Nicole and Grigor reportedly began dating in July 2015, shortly after he broke off his two-year romance with fellow tennis star Maria Sharapova.

Nicole was dating Formula 1 champ Lewis on and off for seven years, with both parties said to be heartbroken when they went their separate ways in May 2015.