Once the adrenaline was spent and the anxiety had given way to exhaustion, José Mourinho's sense of humour clicked in. "They kill me, they kill me," he offered through a smile. "Every game I'm left tired." Managing Chelsea might already carry a health warning, for all the hefty compensation pay-offs flung the way of the departed. Yet, even in victory, there is anxiety to endure when directing the current crop.

Mourinho has been animated on the touchline plenty of times since returning to the Premier League in the summer. He has been ordered from his technical area for constantly overreacting and once even charged across in front of the visitors' dugout and climbed into the East Stand to celebrate a goal with his son, José Jnr. Yet, while overseeing narrow success over a blunt Swansea team, the Portuguese's demeanour betrayed anxiety more than ever. This was pure pantomime. It was no wonder he looked drained.

There were constant bellowed instructions to his players whenever their guard slipped, the manager pacing his technical area and regularly resorting to scream in disbelief at his backroom staff whenever an opportunity, whether a clear-cut or half-chance, was passed up by his players. Steve Holland cowered, sinking further into his tracksuit, while Rui Faria pretended to ignore the histrionics, presumably having seen them all before. At one point Mourinho even started sinking to his calves, as if mimicking André Villas-Boas in that same chalked off area, when another line was fluffed out on the pitch.

Profligacy infects this team and dents their effectiveness. This should have been a stroll against a side whose best opportunity fell to Álvaro Vázquez just after the half-hour mark and was turned away by Petr Cech. "At half-time we all should be relaxed with a comfortable result and we weren't," said Mourinho.

"The first thing that happens in the second half was probably the biggest chance of the game and, after that, we had a clear penalty. If you add all these things up, we should have been comfortable and I could have been relaxed in the technical area and on the bench. But time goes on, we don't score a second goal and the opponents risk a bit more.

"The longer you don't score, the more you feel you are going to concede. At least today I can say the biggest responsibility for the lack of goals was their goalkeeper because he made three or four big saves. He played very well. We didn't miss chances. He saved them." Even so, this all felt familiar. Samuel Eto'o was denied three times, the opportunity 13 seconds after the break from Juan Mata's delicious delivery rather summing up the contest's trajectory. A yard either side of Gerhard Tremmel and the net would have bulged. As it is, Eto'o's volley from point-blank range struck the goalkeeper on the line and Swansea survived.

Those concerns over the strikers will persist, presumably, until the summer when the forward ranks are rejigged. Eto'o, Fernando Torres and Demba Ba boast five Premier League goals from a combined 17 starts this season, although criticising them is becoming a cliché. Chelsea could at least draw encouragement from Eden Hazard's winner, the team's leading scorer fed by Ashley Cole's pass to dart inside Jordi Amat and skim a shot goalwards, which Tremmel might have saved had Ashley Williams not dived across his eye-line.

Hazard was the subject of Mourinho's penalty appeal, too, as Amat dived in to claim the ball but then take the forward's back leg. "Big scissors in the box," said the Portuguese. "The kind of decision other managers cry about for two hours."

In truth, few home players had appeared aggrieved to see the calls waved away, even if it would have lanced the tension. When Swansea did threaten on the counterattack, Ramires scythed down the substitute Wilfried Bony on the halfway line and was booked. "It wasn't a silly action," added Mourinho but it did earn the Brazilian a fifth caution and a suspension for Sunday's visit of Liverpool.

Swansea cursed such cynicism though, appearing to be a side resigned to their own shortcomings. Michael Laudrup's team retain that class in possession but, stripped of the injured Michu, they can be toothless. This loss left them with two wins in 14 matches in all competitions, the Europa League having stretched their resources and disrupted their lineup.

trip to Aston Villa suddenly appears critical, particularly with a collision with Manchester City to come. "We have to take positives from this into the game at Villa," said Laudrup. "But this was what we expected. Teams like that have quality players who eventually make the difference: Oscar, Hazard, Mata, top, top international quality level. There's a reason these players play in certain teams rather than others."

It is upon those players whom Mourinho is leaning, both to create and convert. He had moved to shake Laudrup's hand well before added time had ticked down here, as if desperate for this all to be over. Even in victory, this did not feel enjoyable.