Liverpool had a host of chances to put the game to bed, but failed to find the target to leave Benitez railing.
The Liverpool boss told Setanta Sports: "I can't believe we lost that game, it's as simple as that.
"We hit the crossbar and had a lot of opportunities. It's always important to create chances but it's more important to score.
"We're really disappointed, it was really bad luck. Conceding those two goals is difficult to explain.
"We were controlling everything so I was pleased. We knew we'd have to score the second goal. If we'd scored then they were beaten.
"We had four clear chances in the second half but you have to take your chances.
"We could easily have been 4-0 up after 60 minutes."