Kenny Dalglish attributed our 2-1 defeat to Wigan to tiredness following three games in a week.
Goals from Shaun Maloney (pen) and Gary Caldwell meant Luis Suarez's 12th strike of the season was immaterial to the result.
Dalglish felt having to compete against Stoke last Sunday and QPR on Wednesday took its toll.
"I think we looked a wee bit tired," he said. "We had a lot of possession in the game but we gave away the ball quite a lot in vital positions. It's not because they can't play, it's because of tiredness.
"If you play Sunday-Wednesday-Saturday it's going to take its toll. A lot of the lads had played all three games, and for us that's a reason behind our performance.
"It's because of the demand on them with games, and we've not had enough players at our disposal to give them adequate rest.
"It's a problem we face and it's dictated to the clubs and the players by the television schedule. The fact we've done well in two cup competitions has obviously given us lots of extra fixtures.
"We'll accept our progress in the cups and we'll have to accept that we're going to be a little bit tired. If we're going to be successful we've got to be able to handle it."
Referee Lee Mason awarded a penalty for a high challenge from Martin Skrtel and disallowed another Suarez goal for handball.
Dalglish added: "It doesn't matter how well or badly you play, you still need a wee bit of luck sometimes and there is no reason why the second goal should be chalked off for me.
"But we can't control referees, we can control ourselves. We'll brush ourselves down and get ourselves going again. We've got a week's rest now until Newcastle next Sunday, and we'll make the best of that."
The game was also notable for the debut of 17-year-old Raheem Sterling, who became the club's third youngest ever player.
Jonjo Shelvey and Jon Flanagan were also involved.
"It's nice to see the kids get a game but it's also better for us to look after them," said the boss. "We're not going to throw kids in and destroy them, but it's nice to see them on the pitch.
"Jonjo came on and gave us a wee bit of a lift as well."