Big-serving South African Kevin Anderson battled back to defeat 12th seeded Spaniard Pablo Carreno Busta 4-6 7-5 6-3 6-4 and punch his ticket to his first grand slam final at the US Open on Friday.

Anderson, who in the absence of world number two Andy Murray benefited from a favorable draw, will face either world number one Rafa Nadal or Argentine Juan Martin del Potro in Sunday's final.

The 6ft 8in (2.03m) Anderson climbed into his player's box to embrace his wife, brother and coach Neville Godwin after Carreno Busta's forehand found the net to finish the nearly three-hour contest.

"I don't know if the team hug is appropriate before the final but it felt like the right thing to do," Anderson told the crowd at Arthur Ashe Stadium.

"It's been a long road," added the South African, who overcame a right hip injury last year that had threatened his 2017 campaign.

The 31-year-old, ranked 32 in the world, is the lowest-ranked grand slam finalist since 38th-ranked Jo-Wilfried Tsonga fell at the 2008 Australian Open final.

Anderson was out of sorts to begin with. He hit 14 unforced errors including a backhand that sailed long to hand the composed Carreno Busta a rare break to go up 4-3 in the first set.

The Spaniard closed it out but Anderson settled down after a see-sawing second set and delivered his 20th ace, a 132 mile per hour bullet, to take the third.

The South African's power eventually wore down the 26-year-old Carreno Busta, who had not dropped a set in the tournament prior to the match.

Kevin Anderson of South Africa celebrates his win action against Pablo Carreno Busta of Spain.Kevin Anderson of South Africa celebrates his win action against Pablo Carreno Busta of Spain.