Alexis Sanchez scored twice as title-chasing Arsenal beat relegation-threatened Hull in controversial circumstances in the Premier League.
The hosts had been on top when the ball came off forward Sanchez's hand and ended up in the net on 34 minutes. He added a penalty in injury-time which was awarded after Sam Clucas was sent off for handball from Lucas Perez's header.
In between, Hector Bellerin and Sanchez both failed to hit the target and Mesut Ozil volleyed over the crossbar for Arsenal.
Striker Oumar Niasse had Hull's best chances - his header and low strike forced Petr Cech into sharp saves - while Adama Diomande nodded over late on.
Arsenal had been pressing for the opener before Sanchez's intervention.
The visitors failed to clear Kieran Gibbs' low shot, and as the ball ricocheted off goalkeeper Eldin Jakupovic on the ground it bounced off the Chilean's hand and into the net.
For a deliberate handball, Football Associationlaws state:
there must be "movement of the hand towards the ball"
the "distance between opponent and the ball" should be considered
On this occasion, Sanchez did not look like he purposefully pushed the ball into the net and he had little time to move out of the way after the ball came off Jakupovic.
After consultation with his assistant, referee Mark Clattenburg awarded the goal, but prior to that in the first half, Theo Walcott had a shot blocked by the hand of Clucas inside the area, for which no penalty was given.
After the game, Hull defender Andrew Robertson told Sky Sports that Clattenburg had apologised to the Hull players after half-time.
Robertson added: "The ref told us he didn't give it because he wasn't 100% sure. Not many referees can admit they're wrong, so it's good when he does, though it doesn't make things better."
Decision two goes against Hull - Gibbs' challenge
Chasing the game in the second half, Hull's Lazar Markovic was running onto a long punt forward deep in the Arsenal half.
The Serb was barged down by Gibbs, who was the last defender, and should the on-loan Liverpool man not have been infringed, he would have had a clear run through on goal from 30 yards.
Clattenburg spotted the incident and presented a yellow card.
Gibbs said after the game: "I took a chance with the challenge on Markovic. The ref said the ball was going away from goal."
When asked if Gibbs should have been sent off, Hull boss Marco Silva said: "Yes. It is true. Markovic go to the goal."
Decision three goes against Hull - the second goal
With Hull pushing for an equaliser, they were hit on the counter by the home side. Jakupovic came sprinting off his line as Sanchez went round him and picked out Perez at the back post, but the Spaniard's goal-bound header was kept out by Clucas' arm on the line. Clucas was given a red card for the incident.
Sanchez stepped up to take the penalty, drilling a low finish into the net, which was his seventh goal against Hull in just four games.
It was also his 17th top-flight strike this season, making him the league's leading marksman.
The outlook at the top and bottom
Arsenal had lost back-to-back league games against Watford and Chelsea to leave their title challenge in disarray.
But the win moves them up to third in the table, nine points behind leaders Chelsea.
For Hull, it was an unlucky defeat, having come close to scoring in both halves, but they have now failed to find the net in 12 of their 25 games - more than any other side.
Despite the defeat, Tigers supporters will be buoyed by the impact made by new manager Silva as his side look well-equipped for a battle to stay in the top-flight, yet they remain in the relegation zone by a single point.