West Ham double their lead. Derby are caught short in numbers at the back and Jarred Bowen is free on the right side of the penalty area.
The cross takes a nick off a sliding Craig Forsyth but that just sets it up perfectly for an unmarked Michail Antonio to head past Joe Wildsmith and into the net.
Derby with a mountain to climb now.
Derby's Jason Knight gets the ball on his right foot on the edge of the penalty area and goes for the bottom corner but visiting goalkeeper Alphonse Areola can watch the ball dribble well wide.