Barcelona said Belarussian midfielder Alexander Hleb is expected at the club for a medical Wednesday prior to his transfer from Arsenal.
"If he passes the medical tests, Alexander Hleb could sign a contract tomorrow (Thursday) and be presented as our new player," the Catalan club said on its website.
The Belarussian, who joined Arsenal from VfB Stuttgart in 2005, scored only 10 goals in his three seasons at the London side.
Hleb, who had also been linked with a move to Italian champions Inter Milan, said during an interview in Russia last week that he had told Arsenal manager Arsene Wenger that he did not like living in London and wanted to leave the club.
If the transfer goes through, the 27-year-old would be Barca's fifth signing for the 2008/09 season.
The club has already signed Mali's midfielder Seydou Keita from Seville and three defenders: Spaniard Gerard Pique from Manchester United, Uruguayan Martin Caceres from Villarreal and Brazilian Daniel Alves from Seville.