Pacquiao, who was surprisingly on the wrong end of a points decision against Jeff Horn previous year, is set to take on Lucas Matthysse in Malaysia for a WBA welterweight title this July.
"Contrary to statements which I personally did not make that are circulating in the media, I have not made my final decision who will be my head trainer for my July 14 fight with Matthysse", Pacquiao said.
But Pacquiao went on social media on Monday to say that he would make a decision later this week on his corner team for the Kuala Lumpur fight with the Argentine WBO welterweight champion.
Under Roach's guidance, Pacquiao, who has won world titles in a record eight weight classes, won seven of them with Roach and also was voted the BWAA fighter of the year three times and the 2000s fighter of the decade.
Pacquiao said that Koncz is now in contact with Roach's camp. Amir Khan was the last Roach fighter to walk - after ignoring his advice to watch out for Danny García's left hook in the 2012 defeat that began to unravel the Bolton fighter's career.More news: This is the new Gmail design
More news: Shenmue 1 and 2 are coming to PS4, Xbox One and PC
More news: Shire's $2.4bn cancer sale to make or break Takeda deal
Matthysse said: "This is the fight I have always wanted". I wouldn't trade any of it.
The veteran United States ring guru Roach said last week that his 15-year association with Pacquiao, who has won world titles in an unprecedented eight weight divisions, had been terminated ahead of the Matthysse bout in Malaysia.
In 2001, Pacquiao, then a former flyweight world titleholder unknown to all but the most ardent boxing fan, arrived in Los Angeles looking for a new trainer.
The Friday news release served an update on the fight promotion and included information about an upcoming two-city media tour to Manila and Kuala Lumpur as well as comments from Matthysse about the fight. "The opportunity to fight a future Hall of Famer such as Manny "Pacman" Pacquiao inspires me to work harder than ever to earn a victory for my fans", said Matthysse, who is trained by Joel Diaz.
It is widely thought that 2018 will be the final time Manny Pacquiao steps into the pro boxing ring.