Complex sentence: UEFA.com, 11 April 2003--being nicknamed "Ninja" while playing for the northern side; the following campaign, as he was leading the domestic goalscoring chart, he suffered a severe knee injury which rendered him unavailable for several months.
Split into simpler sentences: UEFA.com, 11 April 2003 He was nicknamed "Ninja" while playing for the northern side. The the following campaign, as he was leading the domestic goalscoring chart, he suffered a severe knee injury which rendered him unavailable for several months.