British number one Dan Evans overcame a strong start by Andy Murray to beat the three-time Grand Slam champion and reach the Battle of Brits final.
Evans was outplayed by Murray in the opening set but won 1-6 6-3 10-8 to set up a final with Kyle Edmund.
Number two Edmund fought back to beat Cameron Norrie 6-7 (3-7) 6-4 10-8.
Meanwhile, Jamie Murray - who has organised the charity tournament - won the doubles final alongside Neal Skupski.
The pair came from behind to beat Evans and Lloyd Glasspool 0-6 6-2 10-6 in the behind-closed-doors event at the National Tennis Centre in Roehampton.
This is an exhibition tournament but the quality has been high and has given players competition practice while the professional tour is suspended because of the coronavirus pandemic.
It has also provided former world number one Andy Murray with a good measure of his fitness, with the 33-year-old Scot playing his first matches in seven months after a pelvic injury.
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Murray's 'best set of tennis for a long time'
Andy Murray got off to a blistering start against Evans, his movement and dominance of the baseline rallies reminiscent of the days when he was world number one before hip surgery stalled his career.
At the changeover at the end of the first set, his coach Jamie Delgado said: "He's played a fantastic set of tennis. It's the best set of tennis I've seen him play for a long time."
But Murray's energy dropped off in the second set, allowing Evans - who also changed tactics to come forward more - to take the match to a deciding tie-break.
World number 28 Evans recovered from a 4-1 deficit in the match tie-break to claim victory with a backhand down the line.
"He did a lot good in the first set. In the end it came down to the big points," Evans told Amazon Prime.
"I got a little lucky today but I'm just happy to come through."
Murray will be reassured by his overall performance, as well as by the fact he has now come through four matches in five days, with one more - a third-place play-off - to play on Sunday.
Edmund fights back to reach final
Like Evans, Edmund was forced to come from behind in his match against Norrie, with the British number three taking the first set and coming close to going a break up early in the second.
But Edmund, who seemed to lack energy in the first set and was sipping cola between some games, turned the tide in the fourth game of the second where he saved six break points.
A break to love in the seventh game Edmund on his way to levelling the match and he edged a tight match tie-break with a winner down the line that left Norrie flat on his back.
Murray wins his own tournament
It is his tournament, so it is probably only fitting that Jamie Murray won a trophy.
But he and Skupski did not make it easy for themselves this week - losing their first group match and then left scrabbling around on their phones to work out if they had done enough to reach the semis after their second group match.
And in the final they carried on making it hard for themselves, losing the first set in 25 minutes without picking up a game before turning it around.
"It's weird to be presenting yourself with the winners' trophy," said Murray, whose event is raising money for NHS Charities Together.
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