Pauleta has told RMC that his former club Paris Saint-Germain can beat Chelsea in next month's Champions League last-16 encounter.
The French champions will host the Premier League leaders at the Parc des Princes in mid-February before heading to West London the following month.
PSG were beaten by the Blues in last season's quarterfinals, succumbing on away goals following a late Demba Ba strike in the second leg at Stamford Bridge.
Pauleta, 41, is confident Laurent Blanc's side can go one better this time round.
"It'll be difficult for Chelsea. In football, anything is possible," he said. "You saw that on Saturday: Chelsea lost against a third-division team. I think that with the squad they have, PSG can do battle with any team.
"There will be two very tight matches against a very strong Chelsea team that is having a great season. I think it's possible to go through, just as it's possible to lose. PSG and Chelsea are two big teams.
"It's always difficult to play against Jose Mourinho teams. He's perhaps the best coach out there right now. He's a coach of great quality, who has very physically and mentally strong teams. But I firmly believe it's possible for PSG to do something."