It would not scan like the original Arsenal terrace chant. “We took a big step towards winning the league at the Tottenham Hotspur Stadium.” The prospect, though, is real. And before Sunday’s derby – the 195th edition of the fixture that determines the mood in north London – it is utterly sickening for Spurs supporters.

Spurs could not stop the Arsenal Invincibles in April 2004 and it is fair to say they have not heard the end of it since. Nor was that the first time their hated rivals had won the league at White Hart Lane. Arsenal did exactly that on the final day of the 1970-71 season when Ray Kennedy’s late header gave them a 1-0 victory.

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It is amusing to re-read the match report from 2004 on the official Spurs website, how it talks up the team’s stirring second-half comeback from 2-0 down, culminating in the “just reward” of Robbie Keane’s stoppage-time penalty for 2-2. The payoff line? “Oh, and Arsenal won the title.”

It cannot happen again. Every Spurs fan knows that and the nerves will surely bubble on Sundaybecause their team have not performed brilliantly over the past five matches, taking in the defeats at Fulham and Newcastle. Arsenal, by contrast, are flying after their 5-0 monstering of Chelsea on Tuesday. They believe that the defending champions, Manchester City, will drop a result to let them in. They have to have that mindset.

Spurs have not lost too many at home to Arsenal in the Premier League (six in 31, to be precise) but they were beaten 2-0 in the corresponding fixture last season and back-to-back defeats are not part of any plan of theirs.

It has even been possible to wonder whether, faced with an either/or question, Spurs supporters would rather Arsenal fall short of what would be a first title since 2004 or their club achieve their own ends for the season – in other words a Champions League finish via league position.

The stars align in that sense on Sunday but there could be a few crises of conscience a week later when Spurs visit Liverpool, who also remain in title contention, and host City on 14 May.

Let us assume that the starting point for any fan is how his or her team do. Moreover, if Arsenal were to miss out, it would not change the reality that they have had another excellent season, one in which they have made further progress, showing they can compete domestically and on the Champions League front, where they reached the quarter-finals.

For Spurs, the related and more interesting question concerns how badly they need Champions League football next season; how much it would really change the landscape for the manager, Ange Postecoglou.

The Fight for Fourth™ is always a major plotline, with Spurs often involved, although it seems to have crept up on us slightly this time, mainly because of the assumption that England would get a bonus spot in the expanded 2024-25 Champions League, meaning fifth in the Premier League would be rewarded.

The realisation dawned suddenly last week, when Arsenal, City, Liverpool and West Ham went out of Europe, that it would almost certainly be Germany taking one of the two extra performance slots, Italy having sewn up the other. And so, drum roll, it is Aston Villa in fourth versus Spurs in fifth; Villa are six points ahead with a better goal difference of five, having played two games more.

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The first thing to say is that, of course, Spurs want the Champions League. It would cast Postecoglou’s debut season in a more favourable light; it would just be better to have than not. It comes down to the primacy of sporting achievement and pride. But then why does there not seem to be the same energy around the battle within the Spurs fanbase as in seasons gone by?

There are numerous factors and as we approach the derby, it is appropriate to mention the one about tribalism; in that Spurs are not fighting for the Champions League against a traditional rival. It would surely be different if it was them or, say, Arsenal for the qualification, as it has been in the past – most recently two seasons ago.

That race turned on Spurs’s 3-0 home win over Arsenal in the third last game and everybody remembers what was said at the time. Spurs were ready to kick on under Antonio Conte while for Arsenal it was a grievous setback for the Mikel Arteta project.

How does the thinking look now? And this is a part of it, too. Spurs supporters have heard the line ad infinitum about the boost in revenues from the Champions League leading to greater clout on the transfer market, bigger signings and finally a title challenge, silverware.

They have had five Champions League seasons since 2016-17, enjoying some truly momentous nights, but they have not made the decisive step at home or abroad. So maybe bear with some of the supporters who have seen the Champions League last-16 exit movie before and wonder whether there might be greater opportunity in a Europa League campaign. Especially as the competition will no longer feature Champions League dropout teams.

This is the slower and steadier development take, which Postecoglou has appeared to support at times; the idea that to go from a season without European football to one with it at the highest level may be too great a leap for a new-ish team. The Europa League has less physical and emotional pressure. It is more acceptable to rotate players.

One key change to the Spurs narrative this season is that they do not have to deliver Champions League football to keep Harry Kane. Would any of Postecoglou’s squad demand a move if they were to remain outside of Europe’s elite competition? He is on record as saying that he does not want players who sign purely for the Champions League.

The manager will be backed with significant funds in the summer but it is unlikely that Champions League revenues would materially alter his budget. The game-changer for Spurs has been the stadium rebuild, which has put the club in a strong and sustainable financial position; also to attract the new investment that the chairman, Daniel Levy, spoke about at the beginning of the month.

Spurs’s season has been coloured by revisionism. Beforehand, with a new manager, half a new team and no Kane, there was not much more than cautious optimism. The Guardian’s writers predicted an eighth-placed finish. But after the stunning start – W8 D2 L0 – a subsequent return of 34 points from 22 matches has been viewed as a disappointment. Transpose that form across 38 games and you get 58.7 points, which would have had Spurs 10th last season.

Overall, there has been progress, even if the bar was lowered by the disaster of last year when the team limped home with 60 points. They have equalled that tally with six matches to play. Against that, there was the run to the Champions League last 16 last season. This season, the domestic cups have again brought failure.

If the fans have bought into Postecoglou as a man and for how he wants to play, it feels as though the harder judgment will be reserved for next season. It will be when we see whether he can lift Spurs upwards from fourth or fifth. Whether he can follow the path lit by Arteta.