Hull - Andrew Robertson's rash challenge undid 72 minutes of hard work by Hull City and allowed Yaya Toure to set Manchester City en route to a 3-0 victory on Monday.
Robertson's trip on Raheem Sterling enabled City to keep pace with impressive Premier League leaders Chelsea, although the early loss of England defender John Stones was a concern.
City manager Pep Guardiola's mood will have been improved when Toure struck from the spot to put the visitors ahead at the KCOM Stadium.
David Silva's low cross was turned in from close range by Kelechi Iheanacho for City's second goal five minutes later and Curtis Davies's own goal with the last kick of the game ended the scoring.
Stones was recalled after being left out of City's previous two league games following a succession of nervy displays.
But he failed to last even 20 minutes, upsetting what had been a bright start by the visitors.
After six minutes, Michael Dawson tripped Kevin De Bruyne and Toure strode up to steer an excellent free-kick over the Hull wall, forcing David Marshall into a one-handed save.
A couple of minutes later, De Bruyne won another corner, this time with a shot from the edge of the area that deflected behind via Tom Huddlestone and through an increasingly crowded home area.
De Bruyne continued the visitors' dominance when he ended a counter-attack by picking out Silva 15 yards from goal and the Spanish international's shot was blocked by Harry Maguire.
City's comfort was disturbed on 17 minutes, however, when Stones went down with a leg injury and had to be replaced by Aleksandar Kolarov.
The adjustment did not cause any immediate problems as Toure's through-ball set up Silva for a shot that, again, tested Marshall, the goalkeeper diving smartly to smother the long-range attempt.
Yet there was no lack of effort or belief in the opening exchanges from Hull, despite their lowly league standing.
On 20 minutes, Jake Livermore headed just over from Ahmed Elmohamady's right-wing cross and, seconds later, the same Hull midfielder tested Claudio Bravo from the corner of the area.
City were becoming increasingly frustrated by Hull's dogged work-rate and when Gael Clichy opted for a more direct approach with a punt into the six-yard area, Raheem Sterling was unable to control.
Nolito also become involved, playing a one-two with Sterling, but his shot lacked the power to concern Marshall.
Hull's supporters applauded their players off at the interval, although it soon became obvious that they would face a long second half.
Sterling opened proceedings with a darting run to the byline and a cross that Marshall palmed to safety from inside the six-yard area.
But, as had been the case in the first half, Hull responded and refused to allow City to settle.
First, Maguire's cross reached Sam Clucas at the far post and his shot was bravely, and painfully, charged down by Bacary Sagna.
A well-worked Huddlestone free-kick was then met by centre-back Maguire on the volley, with his shot flying over from eight yards.
The game was beginning to open up and both teams came close to an opening goal before the hour.
First, De Bruyne showed great footwork on the edge of the area to make room for himself and strike a shot against the foot of the left-hand post.
At the other end, a spell of Hull pressure ended with City failing to clear a corner and Sagna being forced to head Dawson's goal-bound header off the line.
De Bruyne and substitute Iheanacho threatened with half chances before Sterling was awarded the penalty and Toure convincingly buried his shot to the keeper's right. City did not look back.