Borussia Dortmund striker Haller provides health update after starting tumour treatment

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

The former Ajax forward complained about feeling unwell after training on Monday and subsequent tests revealed the tumour with the player set to be out indefinitely as he recovers.

On Thursday, Haller posted a picture of himself on a hospital bed while providing a positive update regarding his treatment.

“Hello everyone, I wanted to let you know that Step 1 has been completed,” he said.

“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."

Haller joined Dortmund from Ajax earlier this month on a four-year deal worth a reported £27million but his diagnosis now leaves the club’s transfer plans in disarray given he will be out for an unspecified period of time.

Dortmund CEO Hans-Joachim Watzke has admitted the Black and Yellow could experience a bumpy ride without the Ivory Coast international but remained coy on whether the club will look for a stop-gap measure before the transfer window shuts.

“It could be bumpy. But we mustn't use that as an excuse in any way, we have to see it as a challenge," Watzke told GOAL Germany on Friday.

"We can't speculate on a player's health before there are crystal clear diagnoses. And it will definitely be several days before that happens."

Haller was set to boost Dortmund’s attack following the departure of Erling Haaland to Premier League champions Manchester City in May.

The former West Ham striker enjoyed a brilliant spell in front of goal for Ajax, scoring an impressive 47 goals in 66 appearances for the Dutch champions since joining them in January 2021.

Haller was the Eredivisie top scorer last season after managing 21 goals as Ajax retained their title and ended the campaign with 34 strikes in all competitions after the Dutch giants reached the KNVB Cup final and the last 16 of the Uefa Champions League.

The player, capped 15 times for the Ivory Coast who he has scored four goals for, was making a return to the Bundesliga where he enjoyed two successful years with Eintracht Frankfurt between 2017 and 2019, scoring 33 goals in 77 games.