Ivory Coast striker Sebastien Haller's testicular tumor has been diagnosed as malignant. The 28-year-old will now undergo chemotherapy, with Borussia Dortmund describing his recovery chances as 'very good.'

Borussia Dortmund have confirmed that striker Sebastien Haller's testicular tumor is malignant.

The Ivorian left BVB's summer training camp earlier this month after complaining of feeling unwell, with a subsequent examination revealing a testicular tumor, which has now been confirmed as cancerous.

Haller will now be out for several months as he undergoes chemotherapy, with Dortmund sporting director Sebastian Kehl describing his recovery chances as "very good."

"Sebastien will receive the best possibl treatment," said Kehl. "We wish him and his family much strength and optimism. Our thoughts are with him in this difficult time."

Back in the Bundesliga

Haller signed for Dortmund from Dutch side Ajax this summer in a deal worth over €30 million ($30.7 million), a transfer intended to help compensate for the loss of star striker Erling Haaland, who has joined Manchester City.

"I'm not here as anyone's successor, I'm here because the club needs my qualities," Haller had insisted.

"He's not quite as fast as Erling [Haaland] but he's a giant striker, so we've not lost any of our weapons," said Dortmund captain Marco Reus.

Between 2017 and 2019, Haller scored 33 goals in 77 games for Eintracht Frankfurt as part of the club's so-called Buffalo Herd along with Ante Rebic and Luka Jovic, as the Eagles won the German Cup and reached the semifinal of the Europa League.

Haller's performances earned him a big-money move to Premier League side West Ham United but he failed to replicate his form, instead moving on to the Netherlands where 47 goals in 65 appearances for Ajax caught the eye of Borussia Dortmund, who brought him back to the Bundesliga.

His testicular tumor isn't the first such diagnosis in the Bundesliga in recent years. Only last week, Hertha Berlin revealed that German forward Marco Richter, 24, would not be taking part in preseason training due to an operation to remove a tumor.

Across the capital, Union Berlin's Timo Baumgartl had an operation on a testicular tumor in May. The player has said he has undergone chemotherapy and is feeling OK, although he has lost his hair.

From Deutsche Welle Newsfeed