"I talked with Fernando on the coach, and that was when I was really convinced that he could play," said Benitez.
"In the morning I had decided that he would be involved, but I needed convincing he could start rather than just be a substitute.
"Playing Fernando was a difficult decision. He was not training, the same as Steven Gerrard.
"But after talking with him we decided it was better to start the game with him.
"We had to be very careful with him, that is why we took him off near the end."
Torres had missed Liverpool's previous two games and also admitted to feeling the effects of his injury during a game in which he took his tally to nine goals for the season.
"I wasn't really at my best," he told the Liverpool website. "We knew before the game I couldn't play to 100% because I had some pain in some actions, but in games like this the pain doesn't matter.
"I feel a bit of pain when I shoot across so I could only shoot towards the near post (for the goal) - it was the only thing I could do!"
Mascherano is in my judgement the leading holding central midfield player in world football - It is inevitable that big clubs will covet a player of that quality
Liverpool managing director Christian Purslow
There is speculation that Liverpool could be forced to sell Torres to help their financial situation but the Anfield club's managing director Christian Purslow eased any such concerns for the Merseyside outfit's fans.
"Fernando signed an extension to his existing contract during the summer," Purslow told Sportsweek.
"He has a five-year contract. He is a crucial leader in our team. He loves Liverpool football club.
"Fernando Torres and Liverpool go together and I believe will do so for the length of his career."
Pusrlow also insisted that midfielder Javier Mascherano, who has been linked with a move to Barcelona, will be staying at the club and not following Xabi Alonso, who moved to Real Madrid in August, in exiting Liverpool.
"No, it's absolutely not true," when asked if Argentina captain Mascherano was keen to leave Liverpool.
"He is in my judgement the leading holding central midfield player in world football. It is inevitable that big clubs will covet a player of that quality.
"We also had another central midfield player coveted by another major world team during the summer and he left us.
"We sat down with Javier at the time. He reasserted his total commitment to Liverpool.
"He has had a lot going on with the Argentina qualification situation for the 2010 World Cup which is now behind him (as they have made it).
"He is a hugely important player for us and a leader."
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