Acapulco, Guerrero, Mexico, 27 February 2016 | AAP

Bernard Tomic took a while to warm up before steaming into the final of the Acapulco Open in Mexico with a three-set win over Alexandr Dolgopolov.

The fifth-seeded Australian was sluggish in the opening set but got into a groove to score a 1-6 6-4 6-3 semifinal victory on Friday.

It was Tomic’s second successive triumph over a Ukrainian following a straight-sets win over Illya Marchenko.

The world No.21 couldn’t go with Dolgopolov early on but found a way to work his way back into contest during the second set.

“He was playing amazing,” said Tomic, who only last week lost in the first round of the Delray Beach Open in Florida to world No.89 Rajeev Ram.

“This is why he’s a very very dangerous player. Many top opponents in the world don’t like to play Alex. He’s very very tough.

“I know Rafa and Novak they say he’s very difficult to play. I knew I was not playing bad but he was playing too good in the first set. So I knew his level of tennis is tough to keep up so I had to stay and try something.”

Tomic will play his fifth career ATP final against the winner of the other semi between Dominic Thiem and Sam Querrey.

Tomic has not played Thiem before and hasn’t lost to Querrey in three encounters.

The 23-year-old Queenslander will be chasing his fourth ATP title – and the biggest of his career to date – to add to crowns won in Sydney (2013) and Bogota (2014 and 2015).