NEW YORK (AFP) -- American teenager Coco Gauff shrugged off disruption from climate protesters to reach the US Open final on Thursday, Sept. 7, as Aryna Sabalenka survived a huge scare to stay on course for a second Grand Slam title.

A night of nerve-shredding semifinal drama saw Gauff reach the final for the first time with a 6-4, 7-5 defeat of the Czech Republic's 10th seed Karolina Muchova.

The 19-year-old Gauff showed great poise to remain unfazed after the match was halted for 49 minutes early in the second set when environmental activists staged a protest in the upper tiers of the Arthur Ashe Stadium.

Play was held up as officials attempted to remove one of the protesters who had glued their bare feet to the concrete floor of the arena. The four protesters were later taken into police custody.

When play resumed, sixth seed Gauff closed out a hard-fought second set to advance to the second Grand Slam final of her career.

The American teenager said while the enforced stoppage had been "challenging", she had sympathy for the activists and their cause.

"I definitely, I believe, you know, in climate change," Gauff said. "I think there are things we can do better.

"I prefer it not to happen in my match but I wasn't pissed at the protesters.

"Obviously I don't want it to happen when I'm winning up 6-4, 1-0, and I wanted the momentum to keep going. But hey, if that's what they felt they needed to do to get their voices heard, I can't really get upset at it."

The protest was the latest high-profile sporting event to be targeted by environmental activists in recent years.

Other Grand Slam tennis events including Wimbledon and the French Open have also been disrupted by protesters.

Sabalenka Houdini act

Gauff, who is now the youngest American woman to reach the US Open final since her idol Serena Williams in 1999, will face second seed Sabalenka in Saturday's final.

The 25-year-old from Belarus, who will take over the world No.1 ranking from Iga Swiatek at the conclusion of the tournament, has been in scintillating form in New York.

But she was forced to come back from the brink to dig out a 0-6, 7-6 (7/1), 7-6 (10/5) win against American 17th seed Madison Keys in 2hr 32min to reach the final.

"I'm really proud of myself that I was able to turn around this game and get this win, because it was just incredible," Sabalenka said after the victory.

"I was just, like, 'Come on, keep trying, keep pushing, like, I don't know, do something extra. Just try to turn around this match.'

"I think this kind of thinking really helped me to stay in the game and to keep trying, keep pushing, to still have this belief that I have a chance to turn around this match."

Sabalenka suffered a disastrous opening set and then fell a break behind in the second to leave Keys serving for the match at 5-4.

But the Australian Open champion roared back to force a tie-break which she won emphatically and then rode her luck in the deciding set, once again recovering from a break down to set up another tie-break.

She was left blushing after mistakenly celebrating victory in the tie-break when she went 7/3 ahead, forgetting the 2022 rule change which dictates that final set tie-breaks are now first-to-10.

"I thought that we play tie-break up till seven," a sheepish Sabalenka admitted. "I was just all over the place."

But she quickly regrouped to close out a Houdini act that had looked improbable after her out-of-sorts display for most of the first and second sets.