WARREN Gatland may have claimed to be in the dark about England debutant Teimana Harrison but Ross Moriarty knows all about him – and hopes to enjoy a similar outcome to his first encounter with the back row forward.

Gloucester flanker Moriarty will win his sixth cap when he joins forces with captain Dan Lydiate and number eight Taulupe Faletau at Twickenham on Sunday (kick-off 3pm).

The 22-year-old, who scored two tries when he came off the bench against Italy in the Six Nations finale following Justin Tipuric's head injury, will have the edge in terms of experience against opposite number Harrison.

Gatland said he didn't know much about the flanker, who enjoyed a breakthrough year with Northampton, but Moriarty has already locked horns with him.

"I played against him in my first game for Gloucester Academy against Northampton and he is a very powerful ball carrier and he will test me this weekend," he said.

"I came off the bench in the last 20 minutes and it was my first experience of English rugby and it was tough.

"He was one of their main players – a very powerful ball carrier and tackler, he was here, there and everywhere. He had dreadlocks then but is still the same sort of player.

"I think I ran over him on a one-on-one – thanks to him I was on the radar of England Under-18s! He may have been a bit more tired while I was fresh off the bench, but it was a good night for me."

Moriarty admits that Wales will have to be flexible in the absence of a specialist openside while captain Sam Warburton continues to rehab a shoulder injury ahead of the first Test in New Zealand on June 11.

The Cherry and Whites star and Dan Lydiate are both primarily blindsides but it is the latter who will be 7 on the teamsheet.

Moriarty said: "I am playing with 6 on my back but we'll be swapping and playing a bit more left and right. It's going to be a bit of a test for us to fit in.

"It is a challenge but we are not going to change the way that we play because of the numbers on our backs. We are both used to being blindside and I don't think you will be seeing too many tackle-jackals.

"I came on early against Italy in the Six Nations and I wouldn't have said I played like a 7, I just played the way that I usually do and that's what I will try to do this weekend."