Andre Villas-Boas claims that the Europa League loses a sense of prestige when teams who have "failed" in the Champions League gain automatic entry to Europe's second-tier competition.
Tottenham finished second in their group with a 3-1 win over Panathinaikos on Thursday and could face one of the Champions League casualties - Benfica, Olympiacos or CFR Cluj - in the round of 32.
But Villas-Boas believes there should be no reward for third-placed finishers in the group stage of the Champions League.
"I think it's extremely unfair," he said. "It would be much fairer if the clubs came in to the Europa League when they are knocked out of the last 16 of the Champions League.
"You can't give a bonus to teams who have failed, and in the situation as it stands, teams fail in the Champions League and are promoted to the Europa League, which, in my opinion, is a massive bonus.
"I've not made this up today. I have said this in UEFA meetings before. It's up to them to decide but I think it's not fair."
Spurs could face Villas-Boas's former side Chelsea if both teams progress past the second round and it is a challenge he would revel in.
"Sometimes it's destiny. Hopefully if we go through we can meet each other," Villas-Boas said. "They have a team that can win the trophy, so they will be up to the late stages of the competition. We hope to do so. If we cross it is going to be two magnificent games for sure."