Spurs moved up into the third place in the Barclays Premier League after Gareth Bale's superb stoppage-time goal secured a hard-fought 3-2 win at West Ham on Monday night.
However, should Arsenal - who are unbeaten in five league matches, winning three in a row - secure victory on enemy territory this weekend, the gap would be reduced to just one point as the race for Champions League qualification hots up.
It has been some 18 years since Spurs last finished above the Gunners in the league, and Diaby - hopeful of recovering from a calf problem to be fit for Sunday - is all too aware of just what this match means for everyone involved.
"We all look forward to these big games because they are not only important to us, but to the club and the fans. It is more than a game," Diaby told Arsenal Player.
"The atmosphere around the game means we all want to win, so that makes it very exciting. That is why I think there are so many goals."
Diaby feels Arsenal can use their 5-2 victory over a 10-man Spurs at the Emirates Stadium earlier this season as leverage when the battle lines are drawn again at White Hart Lane this weekend.
"It will be difficult because they play at their ground and have the crowd supporting them, but we just have to deal with that," the France international added.
"Of course [we have a psychological edge] because from the last game against them we took some lessons and we know them well.
"We know how to deal with them."
However, just how Arsenal will go about trying to shackle the threat of Bale remains to be seen.
Right-back Bacary Sagna was on Thursday ruled out by manager Arsene Wenger with his ankle problem, so Carl Jenkinson could again be asked to step in.
Wenger, though, is hopefully Diaby will be available to add a physical presence to the Gunners midfield.
"It is a question of days. He will have tests and then we will see if we can use him on Sunday or not. It is a 50:50, actually maybe a bit more for him playing," Wenger said.
Arsenal playmaker Santi Cazorla netted both goals in last weekend's 2-1 win over Aston Villa, which kept the Gunners within striking distance of the top four, now just two points behind Chelsea.
The Spaniard cannot wait for another intense derby clash, having been on the scoresheet against Spurs at home in November.
"It is very important, not just because it is a great rivalry or that it is Tottenham versus Arsenal, but the fact that they're a side with great players who are fighting with us for a top four spot," Cazorla said on the club's official website, www.arsenal.com.
"To beat them and get into the top four and the Champions League, which is our aim for the season, is essential.
"We know how important it is and I hope we can rise to the challenge."
Arsenal, meanwhile, on Wednesday night confirmed they would honour former striker Dennis Bergkamp with a statue outside the Emirates Stadium.
Holland international Bergkamp, 43, scored 120 goals for the Gunners as he helped spearhead Wenger's team to unprecedented domestic success as part of the Invincibles' unbeaten Premier League season of 2003-04.
"He deserves that statue," said Wenger.
"I am very happy for Dennis that he gets it. He has what we want to have at the club: dedication, huge desire to win, and a touch of class as well.
"Every single supporter who thinks about Dennis, speaks about class.
"He was completely dedicated to the club. Every day, until the last day of his career, he had the complete 100% focus on every movement he made.
"I believe he had what you need to have if you want to be recognised - print your name in the spirit of people with elegance and class.
"Dennis had efficiency, but he added that kind of elegance that makes people admire you.
"He had something more, and that is very difficult to have when you are a football player."