Where the heck is Gio Reyna?! USMNT star completely absent from Borussia Dortmund squad for DFB-Pokal clash with Stuttgart

Reyna was omitted from Dortmund's 18-man squad on Wednesday, prompting some confusion about his absence. However, the young American has missed out due to illness, with Reyna seemingly the latest to catch a virus that is going around the Dortmund team.

Dortmund boss Edin Terzic revealed on Tuesday that Reyna had a cold and that it "might be tight for him" to play, while Dortmund's website revealed that Reyna is dealing with a virus that previously kept team-mate Salih Ozcan out of action briefly.

The illness comes at a rough time for Reyna, who has struggled for minutes with Dortmund this season. He's featured just five times in the league this season, starting once while only seeing the field for 171 total minutes. He's also played once in the cup and once in the Champions League, totaling 81 minutes between those competitions as well.

As a result, there are rumblings about a possible Dortmund exit, with the 21-year-old midfielder certainly needing more playing time for his development, whether that comes at Dortmund or elsewhere.

Last season Reyna scored seven goals and provided two assists in just 625 minutes, making him the club's fifth-highest goal contributor. That was despite playing half the minutes of all involved as Reyna averaged a goal contribution every 69 minutes, with only Erling Halaand having a better minutes-per-goal ratio in Europe's top-five leagues.

Reyna will hope to recover in time for the weekend when Dortmund face RB Leipzig in a huge Bundesliga match. Entering that game Dortmund sit fifth in the league, with Leipzig just one point ahead in fourth.

After that, the club will look to the Champions League. Dortmund have already sealed a spot in the knockout stage, but it's all to play for their opponents, Paris Saint-Germain, as the 'group of death' will go down to the final matches for PSG, Newcastle and AC Milan.