Belarussian Victoria Azarenka reached her second straight US Open final with a 6-4 6-2 win over Italy's Flavia Pennetta.
Second seed Azarenka, who lost to Serena Williams in last year's final, could get a chance for revenge if top-seeded Williams beats China's Li Na in the Friday's other semi-final.
"I'm so excited. It's been a long road to the final. It's an amazing feeling, to fight for the trophy," said Azarenka, a former US Open junior champion and mixed doubles winner.
Both players struggled to keep their serve on centre court with 13 breaks of serve in the 18 games but Azarenka's power was too much for the enterprising Pennetta, who returned from a serious wrist injury to reach her first grand slam semi-final.
There were five service breaks in a row before Azarenka, the Australian Open winner, held to win the set after an intense battle where the unseeded, 31-year-old Pennetta saved five set points.
The second set followed a similar pattern, with three broken serves before Azarenka turned up the power, holding to go up 3-1 in the set and then breaking Pennetta, ranked 83rd in the world, with a powerful backhand winner.
Azarenka, 24, also struggled to make her serve count though, offering a glimmer of hope to the 31-year-old Italian when she went wide with a return on break point.
But once again Pennetta was unable to hold, twice finding the net to hand Azarenka the chance to serve for the game and despite a brave effort from the Italian, who produced a sizzling return down the line in the final game, Azarenka sealed the win with a well-placed forehand.