Julian Weigl will be sidelined for the next three to four months after suffering a broken ankle in Borussia Dortmund's 1-1 draw with Augsburg on Saturday.
The 21-year-old was injured after a collision with Philipp Max and came off the pitch on a stretcher in the 23rd minute.
Dortmund confirmed the midfielder's injury after the game, writing on Twitter: "Julian Weigl has unfortunately fractured his ankle and will be unavailable for three to four months. Get well soon!"
- Borussia Dortmund (@BVB) May 13, 2017
Weigl made 26 starts for Dortmund in the league this season and was also a regular in their Champions League campaign, with his lone goal of the season coming at Sporting in the group stage.
Dortmund boss Thomas Tuchel told reporters said Weigl's loss was a big blow ahead of Dortmund's DFB Pokal final.
"I saw him with the ball. I can only tell you how I've seen it live," Tuchel told reporters. "I haven't watched a replay of it on TV yet.
"Then they put pressure on him. He wanted to find a solution, but gets fouled from behind. In his next movement his foot gets somehow jammed in the ground.
"Afterwards he told me he immediately felt that something cracked and that something bad had happened. And that's what it is. The first diagnosis says that he broke his ankle joint. That means a break of several months.
"He is playing every game for us and he is playing in the centre, especially in a game like today's. He is always important.
"[Matthias] Ginter really did a great job although he also got hit pretty hard in the beginning of the game. But he fought through that quite long in the game. Now we'll try to find a solution for the two games, but that's going to be really hard."
Weigl will now miss Germany's Confederations Cup participation this summer and face a race to be fit by the start of next season as the Bundesliga resumes on Aug. 18.
He will also likely miss out on the Champions League playoff round if Dortmund finish fourth this season. They lead Hoffenheim on goal difference in the race for third with one game remaining.
And Marco Reus said after Saturday's draw that Dortmund still have it all to play for if they want to ensure they go right to the group stage.
"We actually wanted to win this one," he said. "But even though we only managed a 1-1 draw, it's all still in our own hands.
"We wanted to take a big step towards the Champions League today. Unfortunately that didn't turn out as we'd hoped it would. But we still have a game to go.
"We want to beat Werder Bremen at home as we have the cup final coming up and we don't want to play in the qualifying rounds."