Steve Tandy has admitted there is no hiding from his team's below-par performance ⁠in their 28-21 home Nations Championship victory over Japan on Saturday where they looked flat at times and kept their ⁠opponents in the ⁠contest.

Wales recorded a bonus-point win as Josh Adams twice, Archie Griffin and Louis Rees-Zammit crossed, but they had to produce a desperate rearguard in the final moments to prevent Japan from an equalising score and a famous draw.

"It's a bonus-point win. It's good to start," Tandy said. "I can't run away from the ⁠performance. There are elements we need to improve. I thought we'd be better. We ​weren't ruthless enough."

Tandy suggested rust may ‌have been to blame ‌as Wales played their first Test since July.

"Getting a hit out for the ‌first time since the summer, it does get clunky," he said. "It helps to review after a bonus point win. We'll enjoy it but the beauty of this group is the hunger to get better quicker. We'll definitely have to do that."

Next up for Wales are New Zealand next weekend and Australia. Tandy ‌knows his side cannot afford to offer up cheap opportunities in those games.

"We'd go seven points up and there'd be a ​sloppy moment," he said. "There was some excitement in what we tried to do. Japan were effective close to the line. We managed the game well outside of that. Defensively, we improved."

Wales have now won two of their four Nations Championship games, but stay fifth in the northern hemisphere standings.

Japan's coach, Eddie Jones, felt it was a missed opportunity for his ⁠side, who had 62% of the possession but struggled with entries ​into the Wales 22.

"That ​could have been a historic ​win for us," Jones said. "But you've got to be good enough ​to take advantage ‌of those mistakes. ​We weren't quite ​good enough. It was a missed opportunity.

"I'm proud of my team. We had a young team, but they stuck at it. We had a few times where we didn't take chances and Wales did."

Japan face England on 14 November.