The 52-year-old came through the Hammers' youth ranks in the 1980s, made close to 300 first-team appearances, and then enjoyed a nine-year spell between 2002 and 2011 as a youth, reserve and first team coach at the club (official website).
Keen, who joined Liverpool as a first-team coach under Kenny Dalglish after leaving Upton Park eight years ago, has since held roles at West Bromwich Albion, Fulham, Reading, Crystal Palace and most recently at Southend United.
The retired midfielder, who also had a spell managing Colchester United in 2016, takes over from Jack Collison, who has left the role he has held since 2017, departing to take up a coaching opportunity overseas.
Here is what some of the Hammers faithful made of the club's announcement on Twitter:
He’s a amazing coach— ⚒ Leon ⚒ (@djleon1983) 13 June 2019
Didn’t see this one coming. Great news to have Kevin keen back at the club— mark speller (@supersonic_mark) 13 June 2019
Absolute class coach and what a player he was ! Welcome back !— Paolo (@ellingford_paul) 13 June 2019
Brilliant appointment.— Dan (@WestHamLad) 13 June 2019
Great appointment...best of luck Kevin!— Paul ⚒️ (@72Sawry) 13 June 2019
Welcome home Kevin— Mary (@ZaynafamilyMary) 13 June 2019
Obviously gutted about Jack leaving but wish him all the luck in the world on his new adventures
Good luck Kevin.. welcome back!— Robert Eva (@Rob_Rave) 13 June 2019
Was he 'Keen' to return?— Öscar (@logarythmism) 13 June 2019
Earlier this year, West Ham completed their multi-million-pound redevelopment of Chadwell Heath, while Academy Operations and Player Development Manager Ricky Martin was promoted to the role of Academy Manager, succeeding Terry Westley, who left in early May after five years in the role.
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