Goals by Italian hit-man Rolando Bianchi and Brazilian substitute Geovanni gave the former England boss all three points as his successor Steve McClaren watched from the Upton Park stands, no doubt wishing that some of the Manchester City new boys were English.
Coming into this game, knowing that their new manager had assembled nearly £40 million-worth of players on video evidence alone, the blue half of Manchester must have been as curious as Eriksson to see how quickly his six debutants would settle into hustle and bustle of the Premier League.
But they need not have had any fears as Rolando Bianchi, Elano Blumer, Vedran Corluka, Martin Petrov, Javier Garrido and keeper Kasper Schmeichel quickly got City on top.
Inside the opening quarter-hour, Petrov sent a trio of long-range shots wide before Elano fired over from 20 yards. And on 19 minutes, it was no surprise when City took the lead after Elano's low, right-wing cross into the danger zone was slid home by solo striker Bianchi, who had ghosted into the six-yard box.
Injuries to Scott Parker and Julien Faubert meant that Alan Curbishley had only been able to name two new players in his side as Craig Bellamy and stand-in skipper Freddie Ljungberg made their debuts, while Eriksson's five-man midfield merely added to the Eastenders' frustration.
Indeed, only a valiant double-stop by Robert Green prevented Bianchi from pouncing onto the rebound after Elano unleashed another long-ranger and, it was not until ten minutes before the break, that West Ham finally produced their first tangible effort of the season, when Ljungberg chipped wide of both Schmeichel and his left-hand post.
Curbishley introduced Matthew Etherington and Hayden Mullins at the expense of Luis Boa Morte and the ineffective Lee Bowyer for the restart.
And that double-switch certainly sparked West Ham into more positive mode as Bobby Zamora fired wide after Micah Richards tantalisingly nodded the ball off Bellamy's head underneath the City crossbar.
Then, on the hour mark, Etherington's volley across the face of goal only needed a touch from the outstretched right-leg of the sliding Ljungberg. Midway through the half, Curbishley also introduced the fit-again Dean Ashton following a year-long absence, but while West Ham enjoyed their best spell, City's foreign legion still counter-attacked with pace and power.
But after both substitute Valeri Bojinov and Petrov had excellent chances to double the visitors' lead, Ashton should have equalised after he volleyed Etherington's inch-perfect left-wing cross over the relieved Schmeichel's crossbar.
That was to prove a costly miss for, three minutes from time, Nedum Onuoha teased and tormented his way into through the Hammers' defence before picking out unmarked fellow substitute Geovanni, who sealed a deserved victory for Sven's men with a crisp, low 12-yarder.