Roberto Di Matteo recalled the 27-year-old for his first game as Chelsea caretaker manager in Tuesday night's FA Cup fifth-round replay at Birmingham.
Di Matteo watched Torres miss another presentable chance in a real see-saw performance and must decide whether or not to drop him for Saturday's Barclays Premier League game at Stoke.
Zola, a former team-mate of Di Matteo who regularly tops polls of Chelsea's greatest ever players, reckons the explanation for Torres' misery is simple.
"It's a matter of confidence, obviously," the Italian told journalists.
"To understand exactly what the problem is, you have to be close to him, you have to know him very well - what kind of character he is, how he thinks.
"Only a person who is close to him can understand that.
"From my point of view, he needs to be a little bit more confident and that's all."
One Chelsea player not lacking confidence is Petr Cech, who has insisted he can be the club's goalkeeper for another decade.
Cech, reportedly one of the senior players under threat of being sold in a mass cull this summer, has been criticised for some of his performances this season.
But the 29-year-old believes keepers have a much later sell-by-date than outfield players and says he could go on playing at the highest level until he turns 39.
He told Chelsea Magazine: "In terms of goalkeeping, you need to know that you are still sharp, still strong and that you have good speed of execution in terms of reflex movements and hand-eye co-ordination.
"These are the things you train the most on and they are the results you compare to see if you are still at the same level.
"I think, for an outfield player, it's different because maybe they can't continue to do what they were doing before as they get older and then they need to adjust their game in order to think faster, or something.
"But, as a goalkeeper, I think your reactions can be more or less the same until you are 39.
"It's not about speed so much, so I need to keep the standard of my game all the time, in every aspect.
"Of course, if there is something new to add or something you need to improve, we work on those."