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Great Britain are poised to win their Davis Cup relegation play-off against Ukraine thanks to two contrasting singles victories on day one in Odessa.
Rusedski and Murray put Britain in a dominant position
Veteran Greg Rusedski, 33, saved a match point on his way to a memorable 1-6 6-3 5-7 6-4 9-7 win over Sergiy Stakhovsky, 20, in the opening rubber.
Then Andy Murray beat fellow teenager Aleksandr Dolgopolov 6-3 6-4 6-2.
Rusedski and Murray are due to team up in the doubles but skipper John Lloyd has hinted he may now rest Rusedski.
"Greg says he feels fine but he is on a high right now," said Lloyd, who could pair either Jamie Delgado or James Baker with Murray.
"We will sleep on it and see how he feels in the morning."
Rusedski found himself broken in the fourth and sixth games by Stakhovsky as the Ukrainian raced through the first set.
Mentally I think it is one of my strongest games in the Davis Cup
The Briton fought back in the second, upping his tempo and claiming the crucial break in the sixth game on his way to taking the set 6-3 and levelling the match.
However, he could not maintain his intensity and Stakhovsky got on top once more towards the end of the third set, breaking at 6-5 to edge in front again.
When he raced into a 3-0 lead in the fourth set it looked as though the Ukrainian number one, who lost to Murray in the final of the junior US Open in 2004, was on his way to victory.
But Rusedski roused himself and won five games in a row as he levelled the match once more.
The final set became a battle of attrition, with chances few and far between.
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
Ukraine v Great Britain 0830-1500 BST
Saturday, 23 September
Ukraine v Great Britain 0930-1330 BST
Sunday, 24 September
Ukraine v Great Britain 0830-1330 BST
Stakhovsky saved a Rusedski break point with an ace at 4-3 and three games later Rusedski fought off a Stakhovsky match point with a brave second serve which kicked like a mule off the red Odessa clay.
The crucial break finally came in the 15th game and Rusedski romped though his final service game to give Murray a head start.
"Mentally I think it is one of my strongest games in the Davis Cup and it is where 15 years of experience comes in handy," said Rusedski.
"I did what I had to do out there which was the key. I feel like maybe I am not moving as well as I have been in the past but I still have the spirit out there and that counts for a lot.
"I am stubborn and I refuse to lose. It is hard to accept you cannot do things you have done in the past but you just find a way - and that is what I did today."
Lloyd agreed the win was very special.
"I think it would have to be the greatest Davis Cup performance Greg has played," he said.
I was pretty aggressive when I needed to be
"At this stage of his career, it was unbelievable - an incredible performance."
Murray, the British number one, had a relatively easy ride against Dolgopolov, ranked 452 in the world.
Murray was forced to save break points in the third and seventh games of the opener before breaking in the fourth game and serving out the set.
Dolgopolov, 17, answered by taking a 2-0 lead in the second, showing plenty of deft touches and decent groundstrokes.
But Murray responded in kind and broke back twice to regain control and served out the set.
The Scot was largely unchallenged in the third, again breaking twice to wrap up the match.
"I was happy with the way I played," said Murray. "I was pretty aggressive when I needed to be and I played fairly well up at the net."