Novak Djokovic has suffered four opening-round losses in his last five tournaments, with the latest defeat coming at the hands of Matteo Arnaldi in Madrid.

Novak Djokovic couldn't hide his disappointment after crashing out of the Madrid Open following a shocking loss to Matteo Arnaldi. The 37-year-old went down 6-3, 6-4 to the unseeded Italian and admitted afterwards that he may have played at the tournament for the final time.

Djokovic’s latest loss came on the back of a defeat by Jakob Mensik in the Miami final and what he described as a “horrible” display as he lost in his first match of the Mon