By Josh James at KCOM Stadium
Alexis scored twice - and missed a penalty - as Arsenal saw off 10-man Hull City in an eventful match at KCOM Stadium.
The Chilean deflected Alex Iwobi's shot past Eldin Jakupovic on 15 minutes to give the Gunners a deserved lead after a bright start.
But five minutes before the break Alexis missed from 12 yards after Jake Livermore was sent off for deliberate handball inside the area.
Theo Walcott doubled the lead 10 minutes after the restart, clipping home when one on one with the keeper after a delightful backheel from Alex Iwobi.
The hosts rallied, and pulled one back with a penalty of their own from Robert Snodgrass after Petr Cech felled Dieumerci Mbokani.
But Alexis then quelled any chance of a fightback when he smashed home from close range late on.
The best was yet to come – a scorching strike from Granit Xhaka into the top corner from 30 yards to add a fourth goal.
It ensured a deserved three points for the Gunners, who continued their climb up the table.
Setting the Scene
Since losing on the opening day of the season, Arsenal had built up some momentum, and came into this match looking to make it three consecutive league wins for the first time this calendar year.
Alexis scored the equaliser in Paris on Tuesday to salvage a Champions League draw, and he kept his place up front, looking to continue his excellent form against Hull - he's scored four and assisted two in his four appearances against them so far.
Theo Walcott returned to the starting XI after recovering from injury, while Olivier Giroud missed out completely with a toe injury.
As expected, Petr Cech returned in place of David Ospina after the Colombian impressed in France.
The hosts had named exactly the same starting XI in each of their four league games this season, and caretakermanager Mike Phelan saw no reason to change that formula after his side's bright start to the campaign.
Both teams were playing some fluid passing football in the opening exchanges, as the two sides looked to patiently probe for openings.
But for all the possession football, Arsenal were unable to really threaten the Hull goal until Alexis skied an effort from 12 yards out after being picked out by Walcott.
Walcott was instrumental in the opening goal when it arrived on the quarter hour. His snapshot was pushed away by Jakupovic only to Alex Iwobi, whose first time shot was turned home via a deflection from Alexis.
Arsenal continued to dictate proceedings after taking the lead, with the front players combining well.
Mesut Ozil missed an excellent chance to double the lead just before the half hour. Iwobi struck a fierce shot from just inside the area low to the keeper's right. The Hull stopper made a fine save, and Ozil was unable to tuck home the rebound with the goal at his mercy.
Five minutes before the break Arsenal were awarded a penalty when Francis Coquelin's goal-bound shot was parried by the hand of Livermore. The referee pointed to the spot, and dismissed Livermore, much to the anger of the home fans.
Alexis stepped up to double the lead, but his low shot was too close to Jakupovic, who dived to his right and turned it away.
The home crowd, who had been virtually silenced by Arsenal's first-half goal, found their voice after the break, with referee Roger East the target of their ire.
The hosts were having to leave Hernandez isolated up front as they tried to avoid being outnumbered in midfield.
But the move which led to Arsenal's second goal would have cut through most defences. Iwobi backheeled a through ball to the feet of Walcott, who calmly clipped the ball over the keeper and home, despite the desperate lunge of substitute Harry Maguire on the line.
Arsenal appeared to be in complete control, but out of nothing Hull pulled one back. Substitute Mbokani was brought down in the area by Petr Cech, and after a moment's hesitation the referee pointed to the spot.
Robert Snodgrass smashed home the spot kick and all of a sudden it was game on.
We looked to be in for a nervy last 10 minutes or so, but Alexis smashed home a crucial third goal on 83 minutes.
Theo Walcott broke through only for his shot to be turned away by the keeper. It fell to Alexis in the area who took a touch, steadied himself then rifled the ball home into the roof of the net.
Arsenal could relax again, and the afternoon was given the perfect ending when Granit Xhaka - on as a second-half substitute - blasted home from 30 yards to claim his first goal for the club.
Referee: Roger East
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