The legend of the lasagne lives on. Arsène Wenger was contemplating a nerve-shredding final afternoon of the season, and a three-way tussle for Champions League qualifying places, as thoughts drifted back to baked pasta dishes and the occasion, six years ago, when the bottom fell out of Tottenham Hotspur's challenge at the last. "I didn't cook that day," said the Arsenal manager through a grin. "If I had, more of them would have been ill. But we will certainly be eating here, at the training ground, on Saturday night."

Better to be safe than sorry. That tête-à-tête with bitter rivals in 2006 was the last occasion Arsenal edged into the season's final day unsure whether they would be competing among Europe's elite the following year. The memory of Spurs players dropping like flies in the buildup to their derby at West Ham has become the stuff of folklore, even if it has since been proved that the lasagne, consumed at the Marriott hotel in east London's West India Quay on the eve, was innocent.

Tottenham were actually undone by gastroenteritis, up to 10 players vomiting their way through Martin Jol's pre-match team talk. They ended up drained and defeated while, across town, Arsenal departed Highbury victorious to leapfrog into fourth place.

The scenario on Sunday is more confused. Arsenal travel to Roy Hodgson's farewell party at West Bromwich Albion only a point clear of Spurs and two of Newcastle United. All three clubs will retain hope of finishing third. A fourth-place finish would normally feel satisfactory, but Chelsea can win the European Cup in Munich on 19 May to claim England's last entry into next year's competition and propel the fourth best team in the topflight into the Europa League.

Even if Roberto Di Matteo's team are defeated by Bayern Munich, those in fourth will face a pair of potentially awkward qualifying fixtures early next season which would best be avoided. A fraught finale awaits for all.

Wenger recognises as much. The Frenchman described the game at The Hawthorns as "massive", his own preparations unnerved by recent shoddy form – two wins in seven is unsatisfactory – and a back injury to his goalkeeper, Wojciech Szczesny, which has hampered him for a month and renders him doubtful.

"But I feel we are focused, switched on and I'm confident we'll do well," said the manager. "For us it is just to find the right mixture – to be focused, combative and relaxed, and especially be faithful to play our football like we want to. At the end of the day it will be down to playing well, no matter what is at stake.

"We have known final days like this before, games where we've been playing for titles, or to qualify for the Champions League. We are used to coping with that. It's a fantastic opportunity for us, and one we want to take. If we have more of the ball than West Brom, like we want to have, we will have more chances to win the game. That is what we will focus on. Just be faithful to the way we want to play football."

Such an assessment is fair. Even the frustration generated by that recent stutter cannot disguise the reality Arsenal are grateful to go into the last weekend clear, albeit marginally, of the pack. A glance back at the campaign reveals a traumatic opening, and another stumble in the new year. Spurs felt uncatchable for a while and, when they were 2-0 up at the Emirates stadium in late February, contemplated leading their rivals by 13 points. They have since been reeled in, even if Arsenal will curse a recent inability to finish the job.

Points have been shed unexpectedly to Wigan, Queens Park Rangers, Norwich and Stoke over the run-in to offer Tottenham, who host Fulham on Sunday, and Newcastle, who travel to Everton, hope that third can still be theirs. "But ask our opponents, who were 10 or 15 points in front of us [if it should have come to this]," Wenger said. "Three months ago, everybody would have been happy to be going into the final game with this situation. The Premier League is difficult. We came from a deep position in the league but, if you look at the way we've made to be where we are today, it's remarkable.

"Before this game, we are in a fantastic position and, if we win, we don't need to look at anything else. We want to finish third. We don't want [the worry of the two qualifying games in August], and we have the potential and the opportunity to achieve that now. We're switched on and focused. For long periods this season our fate has not been in our own hands, but it is now. We have to look at this final match as an opportunity, and one we have to take."