Pompey’s victory will ignite hope of survival in the Barclays Premier League.
The result also means Avram Grant maintains his unbeaten record against Benitez after posting two wins and two draws during his time at Chelsea in the 2008 season.
Grant was thrilled to claim the scalp of Liverpool having narrowly missed out to leaders Chelsea in midweek.
“Today we played like a team,” he said.
“From game to game we are playing better and today we deserved the win.
“We played on Wednesday against a team in first place at home, and we showed ourselves if we can do things well at the bottom of the table we can still surprise the other team, and today it went well.”
Pompey midfielder Michael Brown added: “We’ve been playing well in general. It was a fantastic result for us.
“It’s a matter of getting some points and three points is fantastic against a strong Liverpool team with a lot of talent. It’s an enjoyable day for us.”
