In a perverse way, this might have been an afternoon that City will come to regard as hugely beneficial in their bid to sweep the honours board this season, even though it will also be recalled as one of their scarier ones.
Two goals down after half an hour against a side lying 15th in the Championship, they appeared suddenly to be mere mortals, as vulnerable for all their wealth of talent to the possibility of an upset as any other giant to have been felled in the history of a competition still loved best for its fairytales.
Watford, managed these days by a 56-year-old former hospital janitor from Naples, came in the Cup’s best traditions with nothing to lose, took advantage of some rare complacency in City’s quest for success on four fronts and almost reaped a reward they would not forget.
Yet City came through, chastened by some well chosen words from Manuel Pellegrini, a coach whose relaxed, measured public persona clearly conceals a steely side. Sergio Aguero scored twice to bring them level before Jonathan Bond, Watford’s 20-year-old reserve goalkeeper, allowed a shot from Alexander Kolarov to creep under him, handing the home side the lead with three minutes left.
Aguero went on to complete a hat-trick, his second for City, to bring his tally in a remarkable season for him alone to 25 goals in 24 appearances, and City’s aggregate for the season to 110, 72 in 18 games at home. It was by no means comfortable, but Pellegrini’s side will not let their concentration waver again in such a way.
“Was I worried we were going out of the FA Cup? Of course – very worried,” Pellegrini said. “In a cup competition – the FA Cup, the Spanish Cup, the Italian Cup – if you don’t play with 100 per cent concentration and intensity, you will lose the game and the way we played in the first 45 minutes it was impossible to win.
“It is important that the players do not underestimate their opponents, even if they are from the Championship. If Watford had scored the third goal, I think the game was finished.”
Happily for him, City regained their focus and ended the dreams of Watford, whose most optimistic supporters could not have imagined a first half bearing any resemblance to the one they witnessed.
Pellegrini had shuffled his pack, although it was hardly a second-string selection. There was no Alvaro Negredo, nursing a shoulder injury, but Aguero and Edin Dzeko would have looked terrifying enough to Watford’s back four.
Yet City’s concentration seemed suspect from the start as they conceded possession easily to the Championship side. A free-kick given away just outside the box offered Watford a chance in the third minute but Forestieri struck the ball into the City wall. Moments later, after Aguero had given away possession, another chance opened up, with Costel Pantilimon fortunate that referee Kevin Friend saw nothing wrong as he rushed out to claim the ball and collided with Ikechi Anya.
Watford packed their own penalty area and for a while it appeared they had come only to man the barricades, a policy surely doomed to failure. But when they broke, they did so decisively and with pace, the threat they posed compounded by City’s sloppiness in midfield. In the 21st minute, after City surrendered the ball near halfway, Cristian Battochio swept it upfield, Troy Deeney flicked it first time past his marker and Fernando Forestieri, running unmarked into the City box, calmly drove it beyond the reach of Pantilimon.
It was a stadium stunned, apart from the section housing a deliriously happy contingent in black and gold. Yet this was only the first moment of incredulity. Eight minutes later, after Martin Demichelis let Sean Murray seize possession in midfield, Forestieri found Anya and his first-time pass put in Deeney, who swept it past Pantilimon for 2-0.
This was territory occupied only by Bayern Munich at the Etihad this season, the German side being the only other visitors to lead there by two goals. Beppe Sannino, a former player who found work in a hospital among other places before beginning his coaching career in his 40s, pondered possibilities beyond the scope of his imagination.
Yet, ruthlessly in the end, they were dashed. Bond made a fine save from Dzeko on the hour, only for Aguero to tuck away the rebound, then the Argentine, cutting neatly inside his marker, beat him with a curling shot to level the scores.
Bond was unfortunate with the Kolarov shot, which squirmed through his legs off the slippery surface, but even though it was late in the game – only three minutes remained – City were by that point in full flow and Watford were struggling to resist. Aguero’s far-post header in stoppage time, from a Jesus Navas cross, ended all doubts.
Manchester City (4-4-2): Pantilimon; Richards (Zabaleta, h-t), Demichelis, Lescott, Kolarov; Navas, Rodwell (Kompany, h-t), Touré, Lopes (Jovetic, 57); Dzeko, Aguero.
Watford (3-4-3): Bond; Doyley, Ekstrand, Angella; Faraoni (Fabbrini, 84), Battochio, Murray (Abdi, 74), Pudil; Forestieri (Casseti, 60), Deeney, Anya.
Referee: Kevin Friend
Man of the match: Aguero.
Match rating: 8/10