Mircea Lucescu, whose side won the UEFA Cup final last season to set up Friday's annual curtain-raiser to the European club season against the European champions, confirmed the deal was all but done at his pre-match press conference on Thursday.
The player also said he was looking forward to the future at the Nou Camp stadium.
"The deal is done now, I think," Lucescu told the news conference.
"The condition was that he played for us against Barcelona on Friday. It's a great honour for Shakhtar that after winning the UEFA Cup, one of the top clubs in Europe want to sign him.
"He is only 22, nearly 23, a great talent and he will develop very positively at Barcelona.
"When Barca asks for a player it is very difficult to say no, but it is a win-win situation for everyone, the clubs and the player. The only one who loses is the coach as I have to find a new system and build a new team."
Chygrynskiy, who impressed Barca when the two sides met in the same group of last season's Champions League, said: "It is going to be a special game for me, but I am a professional footballer and I will do all I can for Shakhtar in my last match.
"I will put out of my mind the move to Barcelona until after the game, that is a different story. But all I am thinking about now is tomorrow's game."
Earlier Barca sporting director Txiki Begiristain said on the club's website that the deal was not yet finalised, adding: "things are going well and I don't think there will be any problems but it's logical in sporting terms to postpone any agreement until after Friday," he added.
Spanish media have reported the European champions will pay 25 million euros for the Ukrainian who helped Shakhtar beat Werder Bremen in the UEFA Cup final in May.
Barca coach Pep Guardiola, who led his side to a treble last season of Champions League and a Spanish League and Cup double added: "We will speak about the transfer after the game. But it is very important we win it. It is a very big final for us, and it is not every day you play in the Super Cup final."
Guardiola's side has already won one piece of silverware this season by lifting the Spanish Super Cup pre-season trophy and if they win on Friday and then triumph in the World Club Cup competition in December, they will hold six trophies.
"That would be something very special," said Guardiola, "but first we must concentrate on Friday's match."
The only concern for Guardiola was on hearing that the pitch was not in the best of condition.
"I hope that is not the case," he said. "They have had long enough to prepare the pitch and it sould be in perfect condition for a match like this so we can put on a good show for the spectators."
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