A second-half goal from Colombian-born striker Cristian Montano was enough for West Ham to beat local non-league rivals Grays Athletic 2-1 in Sunday's pre-season friendly.
Substitute Montano, who played in the club's youth and reserve ranks last term, netted at the second attempt with 17 minutes remaining and it proved to be the winner.
Jamaican Zavon Hines had put West Ham ahead on 15 minutes but Jamie Slabber, a former Spurs trainee, levelled for the hosts seven minutes later.
It was a mix of youth and experience for the Hammers' first friendly, with Kieron Dyer and Julien Faubert starting in a side led by James Collins. There was no place for Dean Ashton, however, with the striker deemed not yet fit.
Gianfranco Zola made 10 changes at the break with Jack Collison and Danny Gabbidon among those coming on.
The West Ham squad will now head to Austria to continue their build up to the new Premier League season which gets under way with a trip to Wolves on August 15.