Diafra Sakho came off the bench to head West Ham United into the fifth round of the FA Cup this afternoon, scoring the only goal in a 1-0 victory against Bristol City.
The visitors looked as though they were going to have to settle for a replay at Upton Park, until their star striker was introduced from the bench to find a way through eight minutes from time.
West Ham had Mark Noble to thank for keeping the scoreline level when he headed Matt Smith's effort off the line after just six minutes of the tie.
Joe Bryan went close to scoring when he broke into the box before firing an effort across the face of the goal as the League One outfit created the better openings inside the first 20 minutes at Ashton Gate.
Smith was unfortunate again when his header was nodded off the line by Andy Carrol on 24 minutes, while Frank Fielding did well to punch away Carroll's header with Noble lurking.
Carroll forced another save out of Fielding when he poked an effort goalwards from Carl Jenkinson's cross, but the Robins keeper was relatively untroubled as the first half ended all square.
Both sides struggled to find any real momentum following the restart, and it took until the hour mark before West Ham created their first real opening through Stewart Downing.
The England international produced a fine individual run and linked up with Kevin Nolan on the edge of the box, before firing an effort high over the bar.
City themselves probed away in search of an opener and they nearly found one through Smith, who climbed above Winston Reid only to direct his header off target.
Sakho showed a glimmer of hope when he cut in from the left and fired away a shot which came back off the crossbar, but the Senegalese did not have to wait much longer to finally break the deadlock.
Less than 10 minutes of the contest remained when he ghosted in at the back post unmarked to guide a header in off the underside of the crossbar for his 10th goal in 15 appearances for the Hammers.
Home supporters were nearly celebrating an equaliser late on when Smith headed narrowly wide in added time, but it was not to be for Steve Cotterill's men as United saw the game out to seal their progression.