Fernando Alonso has revealed a clutch problem ended all hope of clinching the Triple Crown at the Indianapolis 500.

The two-time Formula 1 World Champion qualified P26 and was bogged down amongst the back markers for much of the iconic race.

Progress was slow and gradual, but Alonso had made his way up to P15 until a clutch failure resulted in some very lengthy pit stops and ensured he finished the race in P21 and a lap down on eventual winner Takuma Sato.

Alonso said he was struggling from the very first lap, with Lady Luck very much not smiling down on him.