The Tottenham Hotspur midfielder was singled out for particular criticism in the wake of an embarrassing 2-1 defeat to Slovenian minnows in the Europa Conference League.
Spurs legend Clive Allen urged the 25-year-old to consider leaving Tottenham having seen his international chances dwindle as a result of his poor form.
However, former Spurs striker Bent went one further and suggested a move away from London could be the best way to revitalise Alli's career.
"I think he needs a fresh challenge somewhere else," he said on Drive. "He looks to me like the world is weighing him down, and it shouldn't do.
"Listen, he is playing at a great football club - great players, great supporters - I think he needs to go elsewhere now. I think he needs to go somewhere and refocus.
"I did it, I left Spurs. I needed to go somewhere where I could just solely focus on playing football and for me, Sunderland was the perfect landing spot.
"Ultimately, the following season I had the best season I ever had, scored 25 goals. But I needed to go somewhere where there was hardly any distractions and I could focus solely on playing football.
"I think Dele Alli is kind of in that situation where he maybe needs to get himself out of London and just focus on playing football again."
Under new boss Antonio Conte, Alli has played one Premier League game and once in Europe - hardly enough time to make an impact.
Yet Bent compared the situation to that of Jesse Lingard, who left Manchester United in January to recapture his form and excelled at West Ham United at the start of the year.
"He's had Pochettino, he's had Mourinho, he's had Ryan Mason, he's had Nuno and now he's had Conte," Bent added.
"I think you just get to a point where you become stale in an environment. He needs to just go anywhere else and start again.
"There is a player there who sows little touches here and there, but right now I am looking at a player that is going stale where he is right now.
"Look at Jesse Lingard; was going stale at Manchester United, goes to West Ham and look at him now. I know he has gone back to not playing, but for those last three months of the season, back in the England squad. That's exactly what Dele Alli needs to do."