Darryl Marfo will leave Harlequins at the end of the season to join London Welsh.
Since joining Harlequins aged 14 and developing through the EPDG and Academy set ups, the 24 year-old loosehead has made 32 senior appearances for the club.
Harlequins Director of Rugby, Conor O’Shea said: “Everyone at Harlequins is delighted that Darryl has got this opportunity. During his 10 years associated with the Club, he has made a huge contribution; we would like to wish him well with London Welsh as he begins the next stage of his rugby career.