Chelsea manager Jose Mourinho admitted his side’s lack of goals in games is starting to take a physical toll.
• Worrall: Chelsea keep pressure on title rivals
The Blues were nearly left to rue their lack of cutting edge against Swansea City but still managed to record a 1-0 victory.
The Stamford Bridge outfit have failed to capitalise on their superior quality in recent times with Mourinho hinting that he may have to revert to defensive tactics to accommodate his misfiring forward line.
But against Swansea, Mourinho believed it was forces outside his players’ control that kept Chelsea from not scoring more than the solitary goal.
“They kill me,” Mourinho said. “Every game I'm tired in the end.
“At half-time we all should be relaxed with a comfortable result and we weren't and the first thing that happens in the second half was probably the biggest chance of the game.
“After that we had a clear penalty, after that the goalkeeper made another fantastic save from [Frank] Lampard's shot, because the ball was going in the corner and had a deflection.
“But the time goes on, we don't score the second goal and you feel like the opponent now believes and the opponent is keen to risk a bit more and put in a second striker. In this moment you are a bit in trouble.
“You don't score, you finish feeling you are going to concede. But the boys, they worked hard defensively and in the last part they looked comfortable in their control of the game.
“Deserved victory, important victory, and today I can say that the biggest responsible for the lack of goals was their goalkeeper, because he made three or four big saves.
“We didn't miss, the goalkeeper made fantastic saves.
“The first half save from [Samuel] Eto'o's shot was brilliant. The first save in the first minute of the second half is the same.
“David's pass just in front of me was good, Mata control and pass was fantastic, Eto'o attacks the ball perfectly.
“My striker made the right movement to attack the ball, he did well, the goalkeeper made a fantastic save.”
Chelsea now turn their attention to a top-of-the-table clash against Liverpool but will be without the services of midfielder Ramires after the Brazilian picked up his fifth yellow card of the season.
However, Mourinho refused to berate Ramires for the caution, believing his player had given his all for the cause.
“It's the kind of yellow card I don't complain to the players because he did it for the team,” Mourinho added.
“I don't want to cry, I just want to think about the solutions we have and prepare the team without him. That's life.
“If I don't play him today to protect him for Liverpool, I wouldn't forgive myself if I lose today points.
“He doesn't play against Liverpool, it means that against Southampton (on January 1) he's fresh.”
Information from the Press Association was used in this report.