Kei Nishikori will be a strong favourite to beat Alexandr Dolgopolov in the final of the Argentina Open on Monday (AEDT) after the top seed came from a set down to end Carlos Berlocq's challenge in his homeland.

Nishikori was in danger of suffering a surprise loss at the Buenos Aires Lawn Tennis Club, but the world number five battled back to win 4-6 6-4 6-3.

A year after Nishikori's last tournament victory in Memphis, the Japanese will be expected to claim his 12th ATP title when he faces the unseeded Dolgopolov.

Berlocq got the first break to lead 5-4 and saved four break points before serving out the set to raise hopes he could pull off an upset.

Nishikori was pegged back from 3-0 in the second, but broke for the second time of asking when Berlocq was serving to stay in the set to level the match.

Nishikori rallied from a break down in the decider to reach his 22nd tour-level final, finally fending off Berlocq in a contest which took two hours and 43 minutes to settle.

While the Japanese star has become accustomed to playing in finals, Dolgopolov will play in his first tournament decider since 2014 after beating Pablo Carreno Busta 7-5 6-2.

The world No.66 from Ukraine has not dropped a set en route to the final and took only 69 minutes to dump out fourth seed Carreno Busta.