Australian Alexei Popyrin has scored one of the best wins of his career, ousting former world No.3 Marin Cilic to progress to his first ATP final.

Former junior French Open champion Popyrin showed his coolness under pressure in Saturday's semi-final, beating the 2014 US Open winner 7-6 (7-5) 7-6 (7-2) to move into the Singapore Open decider.

In Sunday's final, Popyrin will play Kazakhstan's world No.46 Alexander Bublik, who beat Moldova's Radu Albot 2-6 6-3 6-4 in the other semi.

Down 4-1 in the opening set, the big-serving Sydneysider Popyrin broke back before staring down two set points at 5-6.

After a mini-break in the tiebreaker he put his foot down from 1-3 to win six of the next eight points to close out the set.

The Croatian saved five break points in an epic second game of the second set before both the big servers went about their business to ensure this one also went to a tiebreaker.

World No.114 Popyrin exerted his authority early, racing out to a 5-1 lead before eventually shutting down the set and claiming the match.

In all, the Australian served 15 aces, making it 48 for the tournament as he landed his seventh win in nine matches this season.

Popyrin is certainly enjoying a breakthrough year, which also saw him save four match points before downing 13th seed David Goffin at the Australian Open.

Saturday's victory will see Popyrin get back into the world's top 100 when the new rankings are released next week while a win in the final for Popyrin would see his ranking rise to No.82 in the world, a career high.

But 23-year-old Bublik, a big server who can run very hot or cold, is also seeking his first ATP title and could prove a considerable obstacle, having made his second final of the year.

The pair will be meeting for the first time at tour-level but Popyrin can be encouraged by their only previous contest on the ATP Challenger Tour in 2018 in Astana when the Australian rallied from a set down to win in three sets.

Matthew Ebden, who lost in the quarter-finals to his compatriot Popyrin, teamed up with another Australian John-Patrick Smith to reach the final of the doubles in Singapore.

They booked their place with a 6-4 6-4 victory against Venezuela's Luis David Martinez and Spain's David Vega Hernandez in 74 minutes and will play Belgian top seeds Sander Gille and Joran Vliegen in Sunday's final.