Arsenal dominated the opening half-hour of the game at White Hart Lane, but Gareth Bale and Aaron Lennon took advantage of some statuesque defending from the Gunners with two goals in just over two minutes to help Spurs to a 2-1 win.
Tottenham, who now stand seven points ahead of their neighbours, are in the midst of a 12-match unbeaten run in the Barclays Premier League, with their last defeat coming some three months ago at Everton.
Arsenal, on the other hand, have failed to put a decent streak together throughout what has been a difficult season for Arsene Wenger and his men.
Their best run came at the end of 2012 when they went five matches unbeaten and while they scored seven goals against Newcastle and five against Spurs in November, they have also fallen to disappointing defeats to Bradford, Blackburn, Norwich and Swansea.
"On our day we can beat anyone," Jenkinson told Arsenal's website. "I genuinely believe that. When we play to our potential, teams can't come near us, but we need to do that consistently.
"If we do that we will be fine, but we just can't find the consistency at the moment.
"We played well (against Tottenham) in patches, but then we'll have 10 minutes where we'll drift out of the game a little bit."