The Gloucester wing became the seventh Welsh player in World Cup history to score a hat-trick and now has five tries to his name at the tournament, putting him two behind Josh Adams record of seen for a tournament.
“I’ve been taking the mickey out of him because he’s trained every day for six weeks now without missing a training session,” said Gatland.
“That was probably his downfall in the past. He’d have a sore back, or a sore calf – I don’t know if he wasn’t fit enough. But he’s been involved in all the games and we’ve wanted to keep him playing.
“We’re getting the best out of him by having him play and train every day. We’re seeing the benefits of that and we’ve been pleased with his progress.
“There is so much growth in him as a player and I’d like to see him with a little more ball in hand and having a bit of a crack. You see the pace he’s got and he’s very skillful with that kick chase and when the ball’s in front of him.
“He’s a player with a huge amount of potential going forward. He’s still young and we think he can get better and better.”
Commenting on the 43-19 win over Georgia that ensured Wales topped their pool and earned a quarter final against either Argentina of Japan in Marseille on Saturday, he described the victory in Nantes as “a bit messy, a bit ugly, but we got the job done”.
“We had to cope with a few challenges just before kick-off and they are a tough team to put away – there is no doubt about that. I’m pleased we got the result we were looking for,” he added.
“Given Sam Costelow was thrown in at the deep end, I thought he did really well. There were a few opportunities in the first half where he had options to shift the ball, but we kicked out of hand.
“We didn’t want to allow the Georgians to get any soft options to get into us, but there were chances to make inroads when we did have the ball. Tommy Reffell was excellent and we’ve got two outstanding sevens.”
Gatland has now led Wales to two unbeaten pool campaigns at the 2019 and 2023 World Cup tournaments and is now setting his sights on a third semi-final at least in his fourth campaign in charge of Wales.
“We won a pool in 2019 so to repeat that from where we were is a lot of credit to the players and the work they’ve put in with the coaches and support staff,” said Gatland.
“I think we can be pretty proud of what we’ve done as a nation in the last four World Cups – we’ve won 14 out of 16 games in our pools. The very first one was against South Africa when we lost by a point, and we still dispute whether that kick by James Hook was over.
“Then we lost a tight one against Australia in 2015. We probably should have put that game away when they were down to 13 and as a group of players, we should be proud of what we’ve achieved.
“A big part of that is that when we’ve been together as a group, the preparation time and the hard work has helped us in preparation for World Cups. We knew last week that we were in the quarter-finals.
“That probably made today a bit of a challenge because, even though we’ve had the training, there wasn’t that edge that there was for Fiji or Australia.
“But it was enough to get the job done. Sometimes that’s where you see the progress of teams and we can go away knowing it was a little bit ugly at times and we were under pressure, but we got the job done.
“Now we can start focusing on next week.”
