Warren Gatland left baffled as wrong player sent on against Fiji in error

Warren Gatland has said he will look into how Sam Costelow ended up replacing Mason Grady in Wales' defeat to Fiji in Cardiff, after the head coach intended to bring on a different back.

Grady limped off after just 17 minutes of Wales' 24-19 defeat to Fiji in the Principality Stadium - their 10th consecutive defeat at Test level.

The Cardiff wing was replaced by Scarlets outside-half Costelow, who spent 47 minutes on the wing before moving to fly-half after Gareth Anscombe was replaced by Cardiff scrum-half Ellis Bevan with 16 minutes left to play.

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However, Gatland revealed afterwards that the plan, were any outside back to suffer an injury, was for Bevan to cover, rather than Costelow, as he admitted he would likely not replicate the six-two bench split that ultimately left them short in their ninth Test defeat of the calendar year.

"Probably," said Gatland, when asked about whether he would be discouraged by picking just two backs on the bench again. "We were going to get a bit of bad luck and it happened today.

"Probably the wrong player has gone on as a replacement. We talked about Ellis Bevan going on there. That was something we had to deal with.

"It’s difficult. We had a long debate about that and long discussion about the six-two split. The first time you do that and you get caught in the one position you’re a bit vulnerable."

When asked for clarity on whether he meant his comments about Bevan - who scored a try while acting as a makeshift winger - were made with hindsight, he revealed the plan had always been for the Cardiff half-back to cover the outside backs, with the Wales coach clueless over why the wrong change had been made.

"Ellis was supposed to go on," he added. "I need to get to the bottom of that.

"We were talking and said we’re going to put Ellis on. And then Sam’s ran on the field.

"I think he might have assumed he was the person going on. We had already had those discussions with Ellis that if we do lose a winger, you’re going to need to cover us there."