After securing just their third league win of the season, West Ham now face a big test in the EFL Cup as Slaven Bilic's side host an in-form Chelsea team on Wednesday.
The Hammers lost their Premier League season opener against Antonio Conte's men at Stamford Bridge, which triggered off a set of results that left West Ham hovering in the drop zone.
But after beating Crystal Palace and, last weekend, Sunderland, Bilic's men will have been injected with some confidence although the thought of now playing a Chelsea side coming off the back of three straight league victories will be daunting.
The Blues outclassed Jose Mourinho's Manchester United side at the weekend, and despite having to go into the heart of east London to take on West Ham in the Cup, Chelsea will be boosted by the fact they have already beaten West Ham 2-1 this season.
Read on to find out more about the London derby this week...
DATE, TIME AND VENUE
West Ham welcome Chelsea to the London Stadium on Wednesday 26 October, with kick-off set to take place at 7.45pm.
Bilic will have left-back Aaron Cresswell available for selection following his return from knee injury in the 1-0 win over Palace although the game could come too soon for Andre Ayew, who has returned to first-team training following the thigh injury he picked up against Chelsea.
Andy Carroll recently suffered a setback in his attempts to return from an ankle issue while Arthur Masuauku, Diafra Sakho, Gokhan Tore and sam Byram are also out.
Conte will have to assess whether Cesc Fabregas (thigh) and Branislav Ivanovic (muscle) have gotten over their respective issues, although it is likely the Italian will leave the pair out altogether.
Kurt Zouma has returned to training but the defender will not be ready to face West Ham. Willian and Oscar are in contention to feature, however, after the pair returned from Brazil last week following the death of the former's mother and the latter's grandfather.
West Ham vs Sunderland
West Ham likely starting XI: Adrian, Kouyate, Reid, Ogbonna, Antonio, Noble, Obiang, Fernandes, Lanzini, Zaza, Payet.
Chelsea likely starting XI: Begovic, Azpilicueta, Terry, Luiz, Moses, Kante, Matic, Alonso, Willian, Batshuayi, Hazard