Borussia Dortmund striker Sebastien Haller said on Tuesday he was “very moved” by all the messages of support he received after being diagnosed with a testicular tumour. Dortmund said that Haller felt unwell after Monday training and that examinations later in the day revealed the tumour. He has left the team’s pre-season camp in Switzerland and will undergo further examinations at a specialist medical facility over the next days. “I would like to thank you from the bottom of my heart for the many warm messages,” Haller said on Instagram. “I am very moved. But I know that thanks to you, it won…