The 30-year-old, who was formerly in charge of Tottenham's youth team, has joined the Reds' Academy and will be in the dug-out for Saturday's home clash with Middlesbrough, which is live on MUTV with a 12:30 BST kick-off.
McKenna's Spurs side knocked United out of the 2015 FA Youth Cup at White Hart Lane and he has forged an excellent reputation for developing young talent.
New scout in Spain, new scout in the Netherlands and now a new youth coach. Hope this all works out! The recent years hinted that changes were needed in some areas. If those decision are right I cannot judge but the reputation they have, they all seem sensible.
So welcome to biggest club in the world! They all know what we expect...success!