London, England (SportsNetwork.com) - Goals from Morgan Amalfitano and Diafra Sakho helped West Ham to a 2-1 upset win over Manchester City at Upton Park on Saturday.
Amalfitano struck after 21 minutes to put the Hammers in front, and Sakho doubled the lead 15 minutes from time with his sixth goal in as many starts.
David Silva scored two minutes later to cut City's deficit in half, but the hosts held out to claim their fifth win of the campaign, keeping the team in the top four.
City, meanwhile, suffered its second defeat of the season and could fall eight points back of leaders Chelsea if the Blues beat Manchester United on Sunday.
Enner Valencia set up the opener in the 21st when he drove down the right wing and got to the end line before cutting the ball back through the face of goal to an open Amalfitano at the back post for a simple finish.
Sergio Aguero forced West Ham goalkeeper Adrian to make a save with his leg shortly after the hour mark, while the Argentina forward failed to take a great chance as he crashed a shot against the crossbar from six yards after a nice pass from Jesus Navas.
Yaya Toure clipped the outside of the post in the 73rd for City, but West Ham found a second goal a few minutes later as Aaron Cresswell's left-wing cross allowed Sakho to turn a header over the goal line.
Silva answered back quickly for City with a nice individual move to cut the lead to 2-1, but Adrian preserved the win with a nice save in stoppage time to keep out a swerving 25-yard effort from Stevan Jovetic.
Southampton moved into second place after a 1-0 win over Stoke City as the Saints used a goal in the 33rd minute from Sadio Mane to claim their sixth win in nine games.
Arsenal was able to secure just its third win of the campaign on Saturday by downing Sunderland, 2-0, with a goal in each half from Alexis Sanchez, while Liverpool dropped out of the top five after being held to a 0-0 draw at home by Hull City.
Crystal Palace built a 2-0 lead at halftime at West Bromwich, but the Baggies rallied to earn a 2-2 draw with a goal from Victor Anichebe and a stoppage- time penalty kick from Saido Berahino.
The other match on Saturday saw Wilfried Bony score a goal in each half to help Swansea City to a 2-0 win over Leicester City, moving the Swans into sixth place.