Yossi Benayoun concluded his successful loan spell by opening the scoring in today's must-win clash. The Gunners then had to endure a West Brom fightback.
Roy Hodgson's team went 2-1 ahead thanks to a disputed equaliser from a seemingly offside Shane Long, followed by a Graham Dorrans strike in the 15th minute. Yet, despite frequently being criticised for a lack of fight in recent weeks, Arsenal battled back and drew level, thanks to a nice finish from Andre Santos.
The Brazilian left-back was added as part of what many saw as panic buying from Wenger at the end of the summer transfer window. Often ridiculed for the standard of his defending, Santos has still made some crucial contributions during this season, and today's goal was the most vital.
Having restored parity, Arsenal were gifted a winner thanks to a calamity from West Brom deputy goalkeeper Martin Fulop. His ill-judged punch spanned into the path of Laurent Koscielny, who gratefully rolled Arsenal into the Champions League.
Like Santos, the Frenchman endured his share of criticism, as did the man who signed him from Lorient. Wenger was chided for adding a central defender who had played only one season in France's top division. Yet Koscielny overcame some initial struggles and, backed by the persistence of Wenger, has now emerged as Arsenal's most accomplished defender. Accusations of panic buying directly implied that Wenger simply spent recklessly, without any real plan.
Those same accusations also disregarded the calibre of player that Wenger had invested in. Santos and Per Mertesacker are quality, established international performers.
Benayoun's loan deal was sneered at as another shortcut from a manger who can't resist doing things on the cheap. Yet that view ignored the fact Benayoun is a technically gifted player with vital Premier League experience.
Those same qualities were exemplified by Mikel Arteta, whose arrival restored solidity and assurance to a midfield rocked by the departures of Cesc Fabregas and Samir Nasri. Those benefits came at a fraction of the price needed for media and fan favourites like Eden Hazard and Mario Gotze.
Dismissing Koscielny's signing as not having enough star power ignored Wenger's exemplary record of unearthing gems not usually on the radar of other teams. Finishing one place above last season, despite having to rebuild on the fly, shows Wenger's eye for the right player is still as strong as ever.
That's great news as Arsenal seek to find the missing pieces to spark a genuine title challenge next season.