Cameron Norrie beats Stefanos Tsitspas for Hopman Cup win

A shock win for Cameron Norrie over star Greek youngster Stefanos Tsitsipas inspired Britain to victory in the opening tie of the mixed teams Hopman Cup in Perth on Saturday.

Norrie secured the biggest scalp of his career to upset the exciting Tsitsipas in the opening men's singles, but Maria Sikkari then squared the tie with a three-set win over Katie Boulter.

In the deciding mixed doubles, played under the match tie-break format, the Greeks had multiple match points, but it was the Brits who prevailed in three sets.

In the men's singles, world No 200 Norrie upset 20-year-old Tsitsipas in straight sets, 7-6 (10-8) 6-4.

Tsitsipas is one of the hottest young talents in world tennis, having shot from 91st in the world at the start of the year to his current lofty heights of 15th.

He beat Novak Djokovic earlier this year and reached the fourth round at Wimbledon, but looked rusty in his first outing of the new season, although he showed flashes of his best form, particularly the ability to scramble under pressure.

However, the booming forehand of 23-year-old Norrie was a big factor in the match.

The first set was decided in a tie-breaker, with both players holding set points before Norrie closed it out.

In the second set, Tsitsipas went up an early break only for the Brit, who was born in South Africa and has lived in New Zealand and the United States, to break back in the sixth game.

Another break in the 10th game secured the set and match for Norrie, who attended a family wedding south of Perth prior to the Hopman Cup.

The left-hander said it was one of his best wins.

"He came up with some big shots, but so did I and managed to hold my nerve," he said.

"The second set I stayed solid and played well at the end."

In the women's singles, Sakkari came out blazing and won the first set without dropping a game, but Boulter then steadied to level the match.

Two early breaks in the third set laid the foundation for Sakkari to prevail 6-0 4-6 6-2.

The Brits clinched the first set in the mixed doubles, but the Greeks fought back as Tsitsipas adjusted to his first-ever mixed doubles.

The Greeks had the tie at their mercy when they led 3-0 and held their first match point, but the Brits hung in there to win 4-3 (5-0) 3-4 (2-5) 4-3 (5-4).