Brazilian-born midfielder Marlos has received his Ukrainian citizenship and is expected to join the national team on October 2 as it prepares for its final two World Cup qualifiers.
"This is a very emotional moment. I am extremely happy to become a Ukrainian citizen and get the chance to play for the national team. I need some time to learn the language," Marlos told Ukrainian TV on September 30.
Marlos moved to Ukraine in 2012, first joining Metalist Kharkiv before transferring to Shakhtar Donetsk.
Marlos, 29, is expected to join the national team's training camp in Kharkiv on October 2.
Ukraine will play in Kosovo on October 6 and then host Croatia on October 9.
Ukraine trails leader Croatia by two points in its group. Wins in the final two matches will likely secure at least second place for Ukraine.
Group winners automatically qualify for the 2018 World Cup finals in Russia, while second-place teams will enter playoffs for a potential spot in the finals.