Arsenal boss Arsene Wenger feels the outcome of this season's meetings with Tottenham could have a bearing on who qualifies for the Champions League.
Andre Villas-Boas believes his Spurs side "have to" finish above their north London rivals to secure fourth place.
And Wenger said: "The results in the derbies can have a big influence on the Champions League qualifying spot.
"They [Tottenham] are always a team who are fighting with us now and what's important in the end is consistency."
Heading into Saturday's meeting at Emirates Stadium, Arsenal sit eighth in the Premier League - a point behind Spurs after 11 games.
Tottenham have not finished above the Gunners since 1995 and last season let slip a 10-point advantage to end up a place below them.
They went into the second north London derby on 26 February knowing victory would take them 13 points above Arsenal with 12 games left, but surrendered a 2-0 lead to lose 5-2.
But it is a far cry from the early years of Wenger's reign, when he led Arsenal to the title in 1998, 2002 and 2004 as Tottenham finished 14th, 9th and 14th respectively.
"For some time we were winning championships and they were not in the top four at all, so of course they have got closer in recent years," said the Frenchman. "But we managed to always fortunately get above.
"It was later on last year, it was our last chance to catch Tottenham back because if we had lost the game they were out of sight.
"But this year is important as well. Every London derby is very important and we dropped some points recently so want to come back in a more consistent way of results. It's a good opportunity to do that.
"They are a good side, a dangerous side. They are quite physical. With Sandro and [Tom] Huddlestone now in the middle they are stronger physically and still very dangerous on the counter-attacks.
"My chairman knows how much that game means to me and everybody at the club. I've played these derbies for 16 years now so at least I understand the important of it."
The clubs have issued a joint statement warning supporters that anti-social behaviour during the match will not be tolerated.