ALBION suffered a third successive Barclays Under-21 Premier League Elite Group defeat as defensive errors saw them lose 2-0 at Southampton.
The Baggies played well at times on a tricky pitch at Eastleigh FC’s Silverlake Stadium.
But the Saints struck a killer blow when Omar Rowe scored the opener seconds before half-time.
The visitors were unable to create any clear-cut chances after the break and Jake Sinclair added a second for the hosts seven minutes from time.
Albion development coach David Oldfield said: “We enjoyed many good passages of play and passed it well on a difficult pitch.
“There were some good performances by certain individuals but some poor defending cost us both goals.
“Both were preventable, especially the first one.
“We need to consistently do our work and defend collectively.
“The detail makes all the difference.”
SOUTHAMPTON: Gazzaniga, Chambers, Stephens (c), Turnbull, Targett, Robinson (Curtis 68), Moore, Ward-Prowse, Sinclair, Rowe, Seidi (McQueen 74). Subs not used: Johns (gk), Young, Gallagher.
ALBION: Lewis, Hurst, Atkinson, C Jones, Smart, Roofe, O’Neil (c), Allan, Brown (Wedderburn 83), A Nabi, Sawyers. Subs not used: Palmer (gk), Birch, Francis, S Nabi.
GOALS: SOUTHAMPTON – Rowe (45), Sinclair (83).