Liverpool surprised the world last week with a comeback against Borussia Dortmund.
The Reds were 4-2 down on aggregate with half an hour to go before coming back to win 5-4, but Jenas said even before the match kicked off he thought Jurgen Klopp's side would suffer a setback.
Jenas explained that he feels the Reds are now justifiably the bookies favourites to win the Europa League, ahead of their semi-final clash with Villarreal next week.
He said: "I was pretty convinced that Dortmund would have too much for Liverpool, especially when they took the lead, but I've played at Anfield myself when the crowd are in full voice, and as an opposition player you can just feel like you're sinking. It's that loud, even when the side are losing.
"It's that combination of the Klopp factor and the Kop factor that make Liverpool worthy favourites for the trophy."
In Jenas' defence, there were not many brave enough to claim Liverpool could make the comeback against Dortmund, but once they got back level it was clear there would only be one winner.
The manner of the victory has given the Reds a huge confidence boost, and the never say die attitude will have them believing they still have a chance no matter how perilous a situation they find themselves in during the final stages of the competition.