Steven Gerrard gave Liverpool the lead two minutes into the second half but they were pegged back nine minutes later when Liam Ridgewell headed the home side level and visiting fans were left exasperated after Spain striker Fernando Torres was substituted.
Liverpool remain in sixth place with 55 points from 33 games played with Tottenham Hotspur in fifth place on 58 from 32 and Manchester City, who are now favourites to grab fourth after a 6-1 thrashing of Burnley on Saturday, on 59 from 32.
Gianfranco Zola's side, who halted a run of six consecutive defeats despite twice trailing and Mido missing a penalty, have 28 points, one ahead of third from bottom Hull City who have a game in hand. Wigan have 31 points.
"He was exhausted, we played 60 minutes with 10 players the other day," Benitez, whose side will try to overturn a 2-1 deficit at home to Benfica in the Europa League on Thursday, told the BBC.
"(David) Ngog was good for us because he was a pair of fresh legs. His movement was good for the team.
"We had Ryan Babel ready, Dirk Kuyt and Maxi Rodriguez so we had enough people in attack."
"It was a silly goal, when you concede, it is not the best but in this way it's the worst," added Benitez. "The reaction of the team was good, we were attacking and creating a lot of chances. We are disappointed because it was a good performance."
