Murray can not hide his frustration as Britain crash in Odessa

Andy Murray and Jamie Delgado were comfortable beaten 6-3 6-3 6-3 by Orest Tereshchuk and Sergiy Stakhovsky.

Delgado, a late replacement for Greg Rusedski, was constantly targeted as the weak link in the partnership.

The loss means Britain will have to win one of the two singles matches on Sunday to ensure their survival.

"I obviously didn't play at my best today," said Murray. "I didn't serve too well and maybe missed too many reflex volleys.

I played well in my singles on Friday and I have had a great summer and obviously I am expected to win my match on Sunday Andy Murray

"But give credit to them - they looked like they had played together a lot whereas we had only had one previous Davis Cup match together."

Murray will play Stakhovsky on Sunday in a repeat of the US Open junior final which the Scot won 6-4 6-2.

"I am pretty confident because I beat him comfortably in the US Open juniors and I am obviously a much better player than I was then," said the British number one.

"I played well in my singles on Friday and I have had a great summer and obviously I am expected to win my match on Sunday. I think he has also got better but it is down to me to play well."

Things had looked promising for the British pair early on in their doubles encounter.

They gained two break points on the Stakhovsky serve in the opening game of the match but eventually lost the set 6-3.

BBC COVERAGE DETAILS Watch live coverage on BBC Interactive TV via the red button, or follow the tie on the BBC Sport website. Friday, 22 September Rusedski bt Stakhovsky 1-6 6-3 5-7 6-4 9-7 A Murray bt A Dolgopolov 6-3 6-4 6-2 Saturday, 23 September Stakhovsky/Tereshchuk bt Murray/Delgado 6-3 6-3 6-3 Sunday, 24 September Ukraine v Great Britain 0830-1330 BST

Delgado's fallibility on serve was exposed time and again as a far more topsy-turvy second set again fell the way of Ukraine.

The teams swapped breaks of serve at the start of the third set before five wasted break points in a mammoth fifth game and a break of Murray's serve put Ukraine firmly in the driving seat.

The Britons broke back to make it 4-3, but Ukraine again stepped up a gear, breaking Delgado a final time and serving out to seal a crucial victory and send the tie into the last day.

Afterwards, a tearful-looking Delgado could only concede: "I think on the big points those two played pretty well."