The Gunners arrived at Goodison Park wary that defeat to Everton would put the Toffees well and truly in charge of their own destiny in terms of finishing in the final Champions League place, but put in a performance that suggested a huge amount of complacency.
Roberto Martinez opted to play Lukaku on the right side and, with the clueless Nacho Monreal up against him, the Belgium international ran riot. For the second time in Liverpool this season, the Spanish fullback was exposed by a tactical decision that left him horribly lacking support up against a striker with pace and power.
As Brendan Rodgers did with Luis Suarez, Martinez showed Wenger that a manager must be flexible in his system. Having surpassed 1,000 matches in the Arsenal dugout, Wenger is most certainly from the old school. At Goodison he looked positively ancient in terms of tactical nous.
The North Londoners’ insipid showing should not take anything away from the brilliance of Everton, as the Toffees won every key battle.
Lukaku aside, Steven Naismith gave Per Mertesacker nightmares all afternoon with some well-timed runs in behind, while Ross Barkley showed another side to his game with a fine passing display from the heart of midfield.
Barkley, along with defender John Stones, has thrived for Martinez’s side in recent weeks, and both again showed their England credentials with mature displays beyond their years. Places on the plane to Brazil for one, if not both, surely await.
But it was Lukaku who stood out, again adding to the questions surrounding why Jose Mourinho allowed him to leave Chelsea on loan.
In truth, it was games like today that the Portuguese had in mind, as the striker helped take points off one of Chelsea’s title rivals. But with Lukaku's cutting edge in front of goal and hunger to not only score but create goals, one must wonder whether the Stamford Bridge outfit would have had more of a hold on the Premier League with Lukaku in its side.
The season is far from over for Arsenal. It has an FA Cup semifinal in six days against Wigan in a competition that could still see the club finish the season with the silverware its fans crave.
The Gunners then face four sides in the bottom half of the table, as well as a Newcastle United side in freefall, in the stretch run.
A quintet of victories may well see them still poach fourth place from Everton’s grasp, with both Manchester sides still to come to Goodison and a difficult trip to St. Mary’s to play Southampton looming as well.
But for now Wenger must reflect on what could be the defining match of his Arsenal career and the club’s season. Defeat here leaves the Gunners far from assured of Champions League soccer — and Wenger far from secure in his job.
Anything less than a place among Europe’s elite and it may well be curtains for "The Professor."