Borussia Dortmund striker Sebastien Haller completed the first step of his treatment this week after being diagnosed with a testicular tumor.

The 28-year-old's tumor was detected on Monday after he reported feeling unwell to club medical staff.

An immediate medical examination then detected a tumor.

Tumors can be benign and do not always lead to a diagnosis of cancer.

But Haller left Dortmund's pre-season training camp in Switzerland and returned to Germany in order to undergo further tests.

On Thursday, Haller tweeted a photo from his hospital bed in Germany. It showed him smiling and giving a thumbs up.

Haller wrote alongside picture: "Hello everyone, I wanted to let you know that Step 1 has been completed!

"I would like to thank the @BVB and the medical team who were exceptional with me.

"A big thank you also to all the nursing staff of the hospital for their support - benevolence."

Haller has only been a Dortmund player for three weeks.

He signed from Ajax this summer to replace Erling Haaland following the Norway striker's move to Manchester City.

Haller scored 21 goals and provided seven assists in 31 Eredivisie games last season to fire Ajax to domestic glory.

The Ivory Coast international also shone in the Champions League by scoring 10 goals in his first ever six games in the competition.

This article first appeared on FanNation Futbol and was syndicated with permission.

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