Newcastle have signed Japanese prop Kensuke Hatakeyama from Suntory Sungoliath until the end of the season.
The 30-year-old has won 72 international caps and was a part of Japan's World Cup squad that won three of their pool B matches.
In Japan, the tight-head prop twice won the All Japan Championship title.
"Hatakeyama will help us ensure there are no ill effects in our pack with Jon Welsh's injury," director of rugby Dean Richards told the club website.
"He is a very talented player who is a strong scrummager and showed just what he is capable of during the World Cup."