Liverpool manager Rafael Benitez believes his side would be closer to Manchester United in the title race were it not for injuries to Fernando Torres.
The Spanish striker will be missing again with an ankle injury when Liverpool face Sunderland on Tuesday.
“The worst thing has been the injuries to Torres,” said Benitez. “He has been our main striker and scored a lot of goals for us last season.
“And this season could have been totally different with him.”
Torres has played just 15 league games this season, scoring eight goals.
Despite their disappointing domestic form Liverpool a force in Europe, and are on course for the last eight of the Champions League after a 1-0 win at Real Madrid last week.
“The title was difficult before, it is more difficult now,” said Benitez. “What we have to do is take our chances, and that is something that has been the same problem the whole season.
“Maybe if Torres had not been injured so much things would be different, but we cannot change the situation now. Everybody has players who get injured.
“Since the Champions League win in Madrid we have had some problems, several players have been injured, among other things.”
Liverpool captain Steven Gerrard has only just returned after a hamstring injury and Benitez admits his squad lacks the depth of some rivals.
“At this stage of the season when every point is important, having your best players available is the most important thing because they have the experience,” he said.
“It is not fair to expect young players to come in and change games, that is when you need your more important players to bring something more to the side.
“We must keep going in the title race, to try to win each game as it comes along.
“Now we have the opportunity against Sunderland to do things right, to be able to approach the Real Madrid second leg next week with confidence. We have to remain positive.
“We have learned we must be more clinical, to finish games when you have chances.
“But we played with anxiety at Middlesbrough, we gave the ball away too easily with simple passes. These are things we have to improve if we are going to fight for the title.”
And Benitez insists that his side are improving overall, despite seeing their early lead in the title race evaporating.
“We must not forget that our league performance is better than last season,” said the Spaniard.
“Still we have to improve. Yes, we have had key players injured and maybe that could have cost us four or five points.
“In this title race that would be a massive difference. We are in a good position but we could be in a much better position.
“We are now rated in the Uefa rankings as the best team in Europe over the last five years – that underlines how we have done in those seasons.
“But we must go forward for the rest of the season, and in the future. The squad is good, but there are too many games when things go wrong and that makes a massive difference.”