Bayer Leverkusen have announced that Kyriakos Papadopoulos has been ruled out for the remainder of 2014 with a shoulder injury.
The centre-back suffered the injury in the final training session ahead of his side's Champions League match at Zenit St Petersburg, and is set to undergo surgery.
"That's just bitter for Papa," Leverkusen coach Roger Schmidt told reporters ahead of Leverkusen's trip to Russia.
The 22-year-old, currently on a year-long loan from Schalke, only recently returned to action following nearly two years on the sidelines.
Last week, he started his first match since November 2012, and it was his 116th-minute goal that took Leverkusen to the penalty shootout against fourth-tier club Magdeburg and into the next round of the German Cup.
He previously already scored in the reverse fixture against Zenit only minutes after coming off the bench.
At the weekend, Papadopoulos went the full 90 minutes in the 1-0 Bundesliga defeat at Hamburg, but now will not take part in any more games this year.
"The injury requires surgery. That's bitter for us, and especially for him, because he made an impressive comeback, and also scored crucial goals," Leverkusen sporting director Rudi Voller added.
Papadopolous was also an option for Bayer's holding midfield, with Lars Bender currently the last remaining option for coach Roger Schmidt as Gonazlo Castro, Simon Rolfes and Stefan Reinartz are all out injured.
Leverkusen are currently top of Champions League group C with six points, and are followed by Monaco (five points), Zenit (four points) and Benfica (one point).