Albion Reserves fell to their second defeat of the season after throwing away a 1-0 advantage in windswept Norfolk.
They went down 2-1 at Norwich City in a Pontins Holiday Combination League tussle.
Matt Piper put the Seagulls ahead on 35 minutes but the hosts hit back five minutes later and wrapped up the points in the 70th minute.
Albion fielded a youthful line-up laced with a smattering of first-teamers.
Paul Watson, Ross Flitney, Adam Virgo, Dan Harding, Dan Beck and John Piercey have all had first team experience, although their opponents fielded only one player, Clint Easton, whose senior appearance record is in double figures.
Watson was as solid as a rock in defence and showed few signs of the foot injury that has kept him out of action.
The Seagulls made an encouraging start against a strong wind, enjoying plenty of possession and looking crisp in the tackle.
Dan Beck could have scored with just 11 minutes on the clock but saw Canaries keeper Shane Herbert dived bravely at his feet.
The hosts gradually found their feet but no sooner had they settled than Albion were ahead. Beck won the ball on the left, played it inside to Mark Windsor who, in turn, played it across to Piper to tap into an unguarded net.
Olly Willis brought Norwich level five minutes before the break. Ryan Jarvis broke down the left and when goalkeeper Flitney ventured out of his 18-yard box, the striker lobbed the ball into the area where Willis slotted it home.
Albion could have gone ahead again two minutes after the break but Chris Breach's diving back post header from a Watson corner was inches wide of the target.
Beck came close with a good strike from the edge of the area which was deflected just past the post for a corner.
Albion resistance cracked on 70 minutes when Sinclair turned the ball past Flitney from close range.
Albion Reserves: Flitney, Watson, Fillery, Virgo, Breach, El-Abd, Piper, Harding, Beck, Windsor, Piercy. Subs not used: Rents, May, Carey, Elphick.
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