Haller issues emotional statement after testicular tumour diagnosis

thanked everyone who sent him well wishes after he had to leave

's pre-season training camp because of a testicular tumor.

The striker from the Ivory Coast just signed a four-year deal with Dortmund after leaving Dutch champions

. He was brought in to replace Erling Haaland, who went to

Manchester City

.

Haller was training with his new team in Switzerland on Monday when he said he felt sick. Medical tests later found the tumor, so Haller, who is 28 years old, went back to Germany for more tests.

Dortmund has said they will let people know about Haller's health as soon as possible. Haller wrote on Twitter on Tuesday, "I want to thank you again from the bottom of my heart for all the many and kind messages I've received. I've been very touched by the kind things people have said, and I feel I don't deserve so much. But I know that because of you, this will be another test on our way. We'll be back on the field together very soon to celebrate our next wins."

He also said, "I'll work on getting better so I can come back stronger." On Monday,

Sebastian Kehl

, in charge of sports for Dortmund, said that the first test results were "a shock to Sebastien Haller and all of us." Kehl added, "The whole BVB family hopes that Sebastien will get better quickly so we can hug him again soon. We will do everything to ensure he gets the best care possible."

Haller is coming back to German football. From 2017 to 2019, he played for Eintracht Frankfurt. After that, he spent 18 months at West Ham before joining Ajax.

He had a perfect season with Ajax last year. He scored 21 goals in 31 games and was the top scorer in the Eredivisie. He also scored 11 goals in eight Champions League games. Haller has scored more Champions League goals than only Robert Lewandowski (13) and

Karim Benzema

(15).

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