Kevin Nolan rescued West Ham as the midfielder's last-gasp equaliser salvaged a 1-1 draw against Sunderland on Saturday.
Sam Allardyce's side were moments away from their first home defeat of the season after Steven Fletcher's first half goal put Sunderland in control at Upton Park.
But captain Nolan kept his cool to rifle home his third goal of the season just as time was running out for the hosts, who are now unbeaten in their last three Premier League games.
It was a frustrating finale for Sunderland and Martin O'Neill's team are still waiting for their first league win of the season after four successive draws.
Sunderland had taken the lead after just nine minutes as Scotland striker Fletcher claimed his fourth goal in four games since his Â£12 million move from Wolves.
Sebastian Larsson pounced on James Collins' scuffed clearance and lofted the ball back over his head for Fletcher, who cleverly worked space to drill a low shot past Hammers goalkeeper Jussi Jaaskelainen.
West Ham came close to an equaliser after 23 minutes when Nolan's shot on the turn was blocked and Matt Taylor turned the ball back in for Ricardo Vaz Te, whose far-post header was just wide.
The hosts threatened again through Mark Noble, who turned to shoot wide from Carlton Cole's flick.
Vaz Te then combined with Guy Demel to reach the byline and pick out Nolan, whose acrobatic volley was well saved by Simon Mignolet.
Substitute Matt Jarvis teed up Joey O'Brien for a second half shot that was saved by Mignolet and he then caused more panic in the Sunderland box with another teasing cross which earned a corner.
From Noble's delivery, Collins rose well but planted his header onto the bar.
West Ham's pressure finally paid off in the fourth minute of stoppage-time.
Noble launched the ball forward and Jarvis hooked it back to Modibo Maiga, who headed down to Nolan and the former Newcastle star volleyed past Mignolet.