Albion's PL2 side lost 3-1 to Aston Villa at Damson Park on Monday afternoon.
Ollie Bostock made the breakthrough from the penalty spot during the first 45, but after responding with one of their own just before the interval, the visitors capitalised on some errors by the hosts to take the game away from their Black Country counterparts.
Bradley Burrowes converted their spot-kick, while Alfie Lynskey and Rodrigo Fortes struck in the second period to ensure Leigh Downing started his reign as U21 boss with a defeat.
A young Villans team, managed by former Baggies youth coach Jimmy Shan, had the better openings during a scrappy first 45 in Solihull.
Burrowes came closest to an opener - mistiming his run by a matter of seconds to narrowly miss a clever cutback from the right flank, after a sweeping counter attack got the visitors into Albion’s defensive final third.
However, it was in the opposite final third where the first real breakthrough was made by the hosts. Akeel Higgins was kicked in the area, showing good anticipation to beat his Villa counterpart to a loose ball inside the area and earn his side a spot-kick on 32 minutes.
Bostock did the necessary from 12 yards, squeezing the ball through former academy colleague Ronnie Hollinghsead - now between the sticks for the Villans - to hand the young Baggies a 1-0 lead.
That advantage wouldn’t last until the second period, sadly, with the away team winning a penalty of their own in a similar scenario when defender Jamal Mohammed was judged to have connected with a Villa attacker in the penalty area after competing for a 50-50.
He was deemed the guilty party, and Burrowes put his missed opportunity earlier in the game behind him by forcing the ball home from the spot just few minutes before the interval - despite Albion’s trialist shot-stopper getting a hand to the shot.
The second 45 was a case of punished mistakes for Albion's youngsters, as youngster Lynksey edged the visitors in front on the goal line after Villa found space for an opening down the right flank, before Michael Parker's poor back-pass was pounced on and finished off by Fortes to guarantee maximum points for the young Villans.
Albion have a chance to bounce back quickly from defeat when they host Crystal Palace at The Hawthorns on Friday, August 29 (ko 7pm).
Albion: Trialist, Nelson, Mohammed (DuPont 90+2), Parker, Humphries (c), Mfuamba (Bray 63), Crowther, Higgins, McDonald (Mandey 13), Chimeziri (Love 62), Bostock.
Substitutes: Brady.
