Arsenal sealed a controversial 2-0 Premier League win over West Bromwich Albion at the Emirates Stadium.
Mikel Arteta scored both goals from penalties, the first coming after a blatant dive by Santi Cazorla.
Cazorla threw himself to the turf on 25 minutes despite Steven Reid making no contact with his tackle, but referee Mike Jones pointed to the spot.
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There was no doubt about Chris Brunt's foul on Alex Oxlade-Chamberlain to concede the second penalty just after the hour mark, but West Brom felt the England winger had himself fouled earlier in the move.
Arteta clipped both spot-kicks down the middle as Boaz Myhill dived out of the way.
Arsenal ended a three game winless streak in the Premier League, and provisionally move seventh. West Brom remain ahead of the Gunners in fifth despite their third defeat in a row.
Arsenal dominated the early stages without much penetration. Gervinho dragged a shot wide from a Thomas Vermaelen knock-down, while Cazorla also shot off target.
The Spaniard tried the spectacular on the quarter-hour mark when he took an Oxlade-Chamberlain cross on the volley, but blazed it into the crowd.
West Brom struggled to assert themselves, but did go close when Brunt flashed a shot narrowly off target from the edge of the box.
Then came Cazorla's moment of short-term gain but longer-term shame. As the midfielder jinked inside from the left, Reid swiped a clumsy foot - no contact was made, but Cazorla collapsed to the turf and Jones was fooled.
Arteta, who missed a last-minute spot kick against Fulham last month, converted nervelessly.
Though West Brom rightly felt aggrieved about the penalty incident, on the balance of play Arsenal's lead was a just one.
Jack Wilshere should have made it two when he slid in and put an easy chance wide from a Gervinho pull-back, while Gervinho himself brought a good diving save from Myhill with a low shot lacking enough power to find the net.
Oxlade-Chamberlain hit the bar early in the second half with a volley from an outrageously tight angle, but tempered boiled over in the aftermath as Olivier Giroud and Jonas Olsson squared up, with Wilshere also getting involved.
Gervinho missed a golden opportunity to double the lead with an errant header, but soon afterwards Oxlade-Chamberlain won the second penalty.
Oddly, Giroud tried to grab the ball from Arteta, who sent his colleague away and produced exactly the same penalty with exactly the same result.
West Brom's sense of grievance grew as Reid was booked for an innocuous challenge on Gervinho, while Markus Rosenberg had a penalty appeal turned down.
Romelu Lukaku missed a free header to halve the deficit three minutes from time, before Lukas Podolski was guilty of an even worse miss.
Teed up by the excellent Wilshere, the German took an age to steady himself then somehow got underneath the ball and scooped it over from eight yards.
MAN OF THE MATCH
Jack Wilshere (Arsenal) - The young midfielder continues to improve as he returns from long-term injury. Combined slick passing and terrific vision with a fiery competitive streak.
ARSENAL: Szczesny 7, Sagna 7, Mertesacker 6, Vermaelen 6, Gibbs 6, Arteta 7, Wilshere 8, Cazorla 7, Oxlade-Chamberlain 8, Gervinho 6, Giroud 6. Subs: Coquelin N/A, Rosicky N/A, Podolski N/A.
WEST BROM: Myhill 7, Reid 6, McAuley 7, Olsson 6, Ridgewell N/A, Mulumbu 7, Morrison 6, Odemwingie 6, Gera 6, Brunt 6, Long 6. Subs: Popov 7, Rosenberg N/A, Lukaku 6.
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