Felipe Anderson at last began to justify his record price tag by firing West Ham to a 4-2 victory over Burnley.
The Brazilian playmaker was in grave danger of being branded a £42million flop following some anonymous displays since his summer switch from Lazio.
Even Hammers manager Manuel Pellegrini admitted this week that Anderson's performances needed to improve - and it seems he was listening as two well-taken goals secured a deserved win for the Hammers.
It was far from plain sailng for the hosts, though, after they were twice pegged back by goals from Johann Berg Gudmundsson and Chris Wood.
Marko Arnautovic had opened the scoring but, despite a dominant display, they were never assured of the points until Javier Hernandez struck the fourth in stoppage time
James Tarkowski will not remember Arnautovic's goal particularly fondly, especially as he had clattered the Austrian in the opening moments.
Arnautovic got his own back in style after Tarkowski collected the ball and turned towards his own goal, stealing in to collect his under-hit back-pass and slotting home before pointedly celebrating in the face of the embarrassed defender.
West Ham should have been out of sight by half-time but Joe Hart made a fine near-post save to deny Arnautovic.
Burnley were also indebted to Ben Mee, whose stunning headed clearance off the line kept out Anderson's goalbound curler, and to referee Roger East for his failure to give a blatant penalty after Steven Defour brought down Grady Diangana.
It was comfortably West Ham's most commanding 44 minutes of the season, and yet somehow they still went in level at half-time.
From Burnley's first meaningful attack of the match, Ashley Westwood slipped Gudmundsson in behind and the Icelander slid the ball across Lukasz Fabianski and into the net.
Anderson may not even have been playing for West Ham were it not for events at this fixture last season, which descended into a near riot with pitch invasions and protests against West Ham's owners.
David Sullivan and David Gold responded by bringing in manager Manuel Pellegrini and splashing £100million on nine new players, including marquee signing Anderson.
He began repaying a chunk of that fee by collecting Diangana's pass, taking one touch before lashing the ball through Hart's legs.
Yet West Ham have thrown away more points from winning positions than any other team in the top flight this season, and were in danger of being left frustrated again after Wood met Robbie Brady's corner with a bullet header.
Anderson should have restored West Ham's lead moments later only to clip the far post, but when Arnautovic's shot fell to his feet soon after the Brazilian made no mistake.
Even then Burnley could have snatched a point but this time Wood's header grazed the crossbar, and instead Hernandez capped the hosts' victory with a close-range finish at the death.