The Kenyan-born 18-year-old put pen to paper on his first professional contract after catching the eye of Saints Academy coaches Mark Hopley, Will Parkin, Jake Sharp and Tim Grimsey.
He becomes the ninth player to graduate from the club’s Under-18s side ahead of the 2022/23 season.
An athletic back row who predominantly features at No.8 or blindside flanker, Weru has been a part of Saints’ Academy set-up since the age of 14 – scouted originally at Stowe School before he moved to Rugby School to complete his A-levels – and is now training with Phil Dowson’s squad in Northampton with pre-season preparations underway ahead of the new campaign.
“Josh unfortunately had to contend with a couple of injuries last season, so we didn’t see as much of him in the Academy League as we’d have liked, but the considerable impact he made on the pitch when he played proved to us that he has what it takes to make the step up,” said Parkin, who coaches Saints’ Under-18s side.
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“His ball-carrying ability is amongst the very best we’ve seen at Under-18s level, and he still has a huge amount of potential thanks to his natural power and speed.
"Josh has some work to do on the technical side of his game, but he certainly won’t lack the work ethic to develop himself at Saints around studying full-time for a degree in Loughborough.
“We must pass our appreciation to Josh’s teachers from both Stowe and Rugby schools – Mr Seely, Mr Pointon and Mr Bayly – who supported him so well.
"And huge thanks must also go to Josh’s mother, Millicent, and his wider family who have encouraged him to achieve his goals here at Saints.”