Wanjiru was provisionally suspended in April but denied taking a prohibited substance and requested a tribunal. The Athletics Integrity Unit (AIU) has now confirmed the 28-year-old’s ban, in place until 8 December 2023. Details published by the AIU state Wanjiru returned a sample showing levels of red blood cells which had no “physiological explanation”. He was tested 16 times between April 2017 and 2019. In his 14th test – on 9 March 2019 – he showed elevated levels of haemoglobin concentration. It was concluded that the change in levels between tests could not “be explained by any other cause than blood manipulation”. The panel said it was “highly likely” a banned substance or method had been used. Wanjiru won the 2016 Amsterdam Marathon and the 2017 London Marathon.