The Manchester United man feels his Chelsea rival has been performing well of late, even if the goals have not been coming on the international stage, and expects a serious test
The Chelsea man’s form has been questioned recently and he was substituted after just an hour during his national side’s 2-0 win over the Czech Republic.
Scotland need a win over the current world and European champions to grab a place in the play-offs and keep alive their hopes of qualifying for their first tournament since 1998.
Manchester United man Fletcher is insistent that his team-mates need to be aware of the danger Torres possesses, saying that even if he is not scoring for his country, he is still playing well.
"I think his performances have been good since the start of the season," he told reporters.
"Maybe he hasn't had the goals but if you look at his overall performance he has looked hungry, dangerous and lively.
"Maybe he is a little too keen at times. I think his sending-off [for Chelsea against Swansea] was down to his sheer determination to do well and show people that he cares.
"But watching the game against Czech Republic the other night, he did his role for the team.
"He held a high line, he stretched the Czech Republic as much as he could and threatened in behind which gave the space for the creative players to keep the ball in midfield.
"So it was a fantastic performance for the team without getting the rewards of a goal."
It is believed that Vicente del Bosque will field a rotated squad for the clash against the Scots, but Fletcher believes that will not necessarily make it an easier game for the visitors in Alicante come Tuesday night.
"I know from experience that if you change five or six players then it does take a while to get consistency," the 27-year-old said.
"But whoever comes in will be world class and you have the other aspect that whoever comes in will also be desperate to do well, so there are two ways to look at it."
However, Scotland manager Craig Levein does not expect Del Bosque to make too many changes to his team.
Levein said: "There might be one or two who play who did not play against Czech Republic but if you could point out which ones are weak I would be very grateful.
"You know and I know that whoever they bring in will just pose a different type of challenge."
On the subject of Fletcher, Levein stressed the importance of the influential midfielder and sees him as a player that others should look to emulate.
"I think he flourishes with responsibility," he added.
"His importance to this team is almost beyond words.
"Every player in our team will aspire to be as good as Darren Fletcher."