The midfielder fired home in the 63rd minute at The Hawthorns, after Claudio Yacob had given the Baggies a first-half lead.
Elsewhere, Tottenham were stunned 3-0 by West Ham at White Hart Lane, as goals from Winston Reid, Ricardo Vaz Te and Ravel Morrison sealed an impressive away win.
Both games prompted an avalanche of activity on Twitter, and here are our favourite updates, in chronological order.
Former Aston Villa man Ian Taylor (@IanTaylor7) is ready: “Ok….. #WBA v #AFC….. #supersunday”
Celebrity Arsenal fan Piers Morgan (@piersmorgan) is impressed by the Gunners’ free transfer: “Flamini is the new…..Flamini. Makes such a difference having someone protecting the back 4 like this. #Afc Wasn’t happy when we re-signed Flamini. Didn’t like him walking out on us, nor his recent injury record. But he’s been terrific so far. #Afc”
England legend Gary Lineker (@GaryLineker) praises Arsenal’s record signing: “Özil’s first touch consistently and effortlessly gets him in a position where he faces the opposition’s goal.”
No pun intended from former Gunner John Hartson (@JohnHartson10): “Jack Wilshere down and still off the pitch with a bit of smoke in his eye!!”
West Brom’s Steven Reid (@stevenreid12) is thrilled to see Yacob give the Baggies the lead: “Yacobbbbbbb”
Former sprinter Katharine Merry (@KatharineMerry) keeps her followers updated: “Goal…WBA take lead against Arsenal… #pl”
Ex-Ireland international Kevin Kilbane (@kdkilbane77) is enjoying the game: “Can #afc respond to the #wbafc goal from Yacob? Very good game here at the Hawthorns today on @bbc5live”
Golfer Ian Poulter (@IanJamesPoulter) is multi-tasking: “Watching the Arsenal game in my indoor studio hitting balls on my @FullSwing simulator. 2 birds with 1 stone. Then flying to Carlsbad later
Morgan (@piersmorgan) calls on Arsenal to move up a gear: Baggies playing well. Need to step it up Arsenal. #Afc
And Wilshere duly responds with the equaliser, with Morgan (@piersmorgan) adding: BOOM! 1-1. Like I said, Wilshere’s a great player and Arsenal will prevail. #MysticMorgan #Afc @JackWilshere”
Cue another pun from Lineker (@GaryLineker): “Wilshere, Smoking!
Boxer Anthony Ogogo (@AnthonyOgogo) is impressed by Youssouf Mulumbu’s challenge on Jack Wilshere: “That’s a world class tackle from Mulumbu, that’s how you tackle.”
After the game finishes 1-1, injured Arsenal striker Yaya Sanogo (@OfficielSanogo) chimes in: “Unfortunately a draw against WBA. But Still 1rst! #afc #arsenal #arsenalfc”
Arsenal striker Olivier Giroud (@_OlivierGiroud_) felt the Gunners could have won it: “Tough game, came back well in 2nd half and were so closed to win it.. btw still top of the league! Amazing crowd today!”
Midfielder Jack Wilshere (@JackWilshere) was delighted to get on the score-sheet, prompting chants of ‘he smokes when he wants…’ from the away fans: “Love the new song for me today! Haha fans were incredible again! Good point nice to get a goal hopefully a few more to come! #Gooners”
Midfielder Aaron Ramsey (@aaronramsey) hails the travelling fans: “Great support from our fans today. A point at a form team and still top heading into the international break #AFC”
Record signing Mesut Özil (@MesutOzil1088) is happy to be back on top of the table: “One more unbeaten game, two weeks more leader – wonderful time in London. #afc #Arsenal #gunners”
And Nicklas Bendtner (@bendtnerb52), who was a late substitute, was pleased with the result: “Great response from 1-0 down! character and belief got us back in it. Probably a fair result. #arsenalfc #firstPLapperence #nowitsdenmark”
Meanwhile, Spurs’ defeat at the Lane doesn’t impress David Ginola (@DavidGinolaCeze): “Come on Tottenham you’re better than that…”
Nor Lord Sugar (@Lord_Sugar), who is shocked: “Can you believe result? 0-3. Prior to kick off West Ham people in boardroom saying they had no chance.I was telling them to enjoy lunch”
And finally, former Tottenham striker Lineker (@GaryLineker) praises Sam Allardyce’s Hammers: “Superb result for West Ham, and by all accounts a sensational goal from Ravel Morrison. Great to see him realising his enormous potential.”
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