The Chicago Fire FC's Gabriel Slonina, an 18-year-old viewed as a goalkeeper of the future for the U.S. national team, was listed on Poland's 39-man roster announced by coach Czesław Michniewicz on Tuesday ahead of four Nations League matches next month.

Sources have told ESPN that there is "no update yet" on whether Slonina will accept the call-up.

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Slonina, who turned 18 on Sunday, became Major League Soccer's youngest starting goalkeeper last Aug. 4 at 17 years, 81 days, in a 0-0 draw against New York City. He started 11 league matches last season. including the final 10, and has started the first 11 this year.

Born in Addison, Illinois, and of Polish descent, Slonina attended U.S. national team training camps in December and January but did not get into any matches. He has played for the U.S. at several youth national team levels.

Under FIFA rules, a player may appear into up to three matches for a national team before turning 21 without being tied to the team.

? POWOŁANIA ??
Selekcjoner Czesław Michniewicz ogłosił listę powołanych zawodników na czerwcowe mecze Ligi Narodów. ?
⚠️ Mamy debiutanta! ⤵️ pic.twitter.com/A8yayYb0l6

— Łączy nas piłka (@LaczyNasPilka) May 17, 2022

Slonina is among five goalkeepers on Poland's roster, joining starter Wojciech Szczesny of Juventus and Bartłomiej Drągowski of Fiorentina, Kamil Grabara of FC Copenhagen and Lukasz Skorupski of Bologna.

Zack Steffen of Manchester City and Matt Turner of New England, who is transferring to Arsenal this year, shared the U.S. starting job during World Cup qualifying, and Ethan Horvath and Sean Johnson also were on the roster.

Poland hosts Wales on June 1 and Belgium on June 14, and is at Belgium on June 8 and the Netherlands on June 11.

ESPN's Jeff Carlisle contributed to this report.