The Baggies provided most of the running against a much-changed Canaries lineup with youngster Jed Steer in particular impressing with a number of quality saves for his team
The home side did all the running in the game but couldn’t make their dominance pay as Grant Holt gave the visitors the lead in the first half with a neat header before Marc-Antoine Fortune easily side-footed home an equalizer. However, Jackson then capitalized on a shocking error from Albion’s Craig Dawson to slide the ball across Ben Foster and send the away fans into raptures.
Roy Hodgson made three changes at the back with Gonzalo Jara, Joe Mattock and Craig Dawson all coming in for Jonas Olsson, Nicky Shorey and Gareth McAuley, while Simon Cox and Fortune were kept up front.
Norwich showed five changes from its last game as Jed Steer, Adam Drury, Elliot Bennett, Andrew Crofts and Wes Hoolahan all came in to replace John Ruddy, the ineligible Kyle Naughton, Steve Morison, Andrew Surman and Bradley Johnson.
Both teams began the game cagily, much as they had done in the Premier League two weeks ago, when Morison scored a late winner to seal the match 2-1.
Such was the dourness of the opening moments of the game that it took nearly 20 minutes for the first shot to be fired towards goal, and this could be put down to the multiple changes that both managers made as they clearly had one eye firmly placed on the Premier League.
When the first shot did come in City’s young goalkeeper Steer had to be alert to expertly tip a Jerome Thomas effort on to the bar from 12 yards out after good work from Jara found the winger at the back post.
The home side then began to dominate as the much-changed Norwich struggled for fluidity. First James Morrison put his shot wide of the left hand post when well-placed on the edge of the area before Fortune should have done better with a header that went harmlessly over the bar.
Against the run of play the away side took the lead in the 35th minute with its first chance as Hoolahan fed winger Bennett on the right hand side before his drilled cross was taken well at the back post by Norwich skipper Holt for his ninth goal in all competitions this season.
The Baggies began the second half with great purpose as they tried to get back into the game and the equalizer duly came in the 54th minute from Fortune.
Joe Mattock's chipped ball down the left was dithered on by Russell Martin which allowed Jerome Thomas to cut in from the left and feed the striker, who side-footed the ball past Steer at his near post with consummate ease.
The home side continued to dominate, much as it had done in the first half, but it couldn’t quite find a way past some resolute City defending and the impressive Steer in goal.
Super-sub Jackson then robbed Dawson of the ball with five minutes left on the clock and drove towards goal before firing the ball across Foster to seal the team’s route into the next round of the FA Cup.
Norwich then somehow survived a couple of goal line scrambles, with Steer ensuring his side won the game with a fantastic save from substitute Shane Long at the death.