The 26-year-old has been very inconsistent with his performances this season, and Jenas has singled him out for criticism during Tottenham’s defeat against their London rivals.
Spurs lost 2-0 against Frank Lampard’s side in the Premier League on Sunday at home. Brazilian winger Willian scored both the goals for the Blues.
The north London club were outclassed by Chelsea in the first half. Aurier conceded a silly corner and Willian opened the scoring from his mistake.
“From a Spurs point of view, it was schoolboy like. That’s the only way I can explain the defending,” Jenas told BBC Radio 5 Live.
“What Serge Aurier was doing with the header initially to give away a corner and then they were slow to get out to Willian. Makes no sense.”
It was a comfortable victory for the Blues against Jose Mourinho’s side but the game was overshadowed by alleged racist behaviour aimed at Antonio Rudiger.
Chelsea’s victory strengthened their grip on fourth place, while Spurs remained in seventh place – six points adrift of the fourth spot.