At 14 years old, Weru joined the
Northampton Saints Academy. On the 3 August 2022, Josh Weru signed a professional contract with Northampton Saints after graduating from their Under-18 set up. His main strength was his ball carrying ability with academy coach, Will Parkin saying: “His ball-carrying ability is amongst the very best we've seen at Under-18s level”. Unfortunately, late in 2022 he lost his contract with
Northampton, before he managed to debut for the senior team, due to his aspirations to play for the
Kenyan National Team. Under the
RFU's eligibility criteria, to secure a working visa to play professional rugby, a player from a Tier 3 nation (such as
Kenya) has to have a minimum of 10 international Test caps, of which three must be played during the previous 24 months. In December of 2025, Weru was named to the
NFL's
International Player Pathway program, making him a prospect in the
2026 NFL Draft. In April 2026 Weru was signed by the
Philadelphia Eagles of the NFL as an undrafted free agent. == International career ==