Why was Shanaka not given run out in the Super Over drama?

Why was Sri Lanka's Dasun Shanaka ruled not out even though he was run-out by Sanju Samson off the fourth ball of the Super Over against India in the Asia Cup game on Friday?

For a while, confusion reigned when Shanaka ventured out of his crease after missing a yorker from Arshdeep Singh, who went up in an appeal for a caught behind, while Samson threw the ball at the stumps to find the batter short. But the umpire had given Shanaka out caught behind after a bit of contemplation, and Shanaka referred the decision upstairs to the third umpire Masudur Rahman. After replays confirmed there was no bat involved, Shanaka was ruled not out for the caught behind and for the run out too. It was the timing of the umpire signalling out initially for the caught behind - after Samson's direct hit - that led to the confusion.

MCC's law states that "the ball will be deemed to be dead from the instant of the incident causing the dismissal". In this case, that incident was the caught-behind appeal, which meant the ball had been dead when Samson tried to run Shanaka out. With replays proving Shanaka didn't nick the ball, he was immediately deemed not out, even though India captain Suryakumar Yadav seemed to enquire with the umpires about the decision.

"According to the rules, if you appeal for the catch, then Dasun could go up to the third umpire," coach Sanath Jayasuriya said of what he made of the appeal. "It was the first decision that counts always, not the second. So he went for the referral, and it was not out. That's what happened. But overall, I think there are a few grey areas [in terms of the rules at large] that they [officials] have to finetune a bit."

However, Shanaka was out next ball when he sliced one to deep third as Sri Lanka lost both their wickets five balls into the Super Over to set India just three runs to go into the final unbeaten. Suryakumar then thumped Wanindu Hasaranga first ball through the covers to seal India's victory.