Sporting Lisbon 0 Chelsea 1

The scoreline might suggest this was a squeeze, an awkward evening of defensive resilience and a lead pilfered on the break, but that would be wildly deceptive. Chelsea actually delivered something akin to a thrashing by a solitary goal in Lisbon to make their first proper statement of intent in this group. José Mourinho appeared mystified at times that his side’s dominance was not being properly reflected but this had in reality been a happy homecoming.

It was hard at times to comprehend quite how the visitors failed to score a hatful as Sporting Lisbon heaved to contain them, only for profligacy to ensure an anxious ending.

Perhaps they were dizzied by the laser pens shone from the stands into a number of visiting players’ eyes over the course of the evening. The management will not use that as an excuse when analysing quite why this tie had not been dispatched far earlier. A bigger lead would have allowed bodies to be rested before Sunday’s visit of Arsenal. As it was, Mourinho has been denied that privilege.

This had been billed, perhaps optimistically, as a stern test of Chelsea’s credentials, a confrontation with opponents relishing a recent renaissance and played out to a raucous din from the stands.

Sporting had been impatient for this moment, a first home game in the Champions League proper since they were humiliated 5-0 by Bayern Munich in a last-16 tie back in February 2009. They had gone 16 games unbeaten here since in the Europa League or qualifiers, but none of those games had been against opposition of this calibre.

So clear-cut were the opportunities prised out by the visitors from the outset that Sporting’s proud record should have been in tatters long before the interval. As it was, they still retired behind then and somewhat scorched by the whole humbling experience.

There were gaping holes in the Portuguese side's ragged back-line from the opening exchanges, the yawning distance between the centre-halves, Mauricio and Naby Sarr, enough to have Cesc Fabregas and Oscar – players always spying a delicate through-ball – drooling while William Carvalho struggled with his bearings at the base of the home midfield. He was eventually booked for bringing down Eden Hazard, the only surprise being he had been able to locate the Belgian to make illegal contact.

Sarr, another youngster secured from Lyon, also struggled with Hazard whenever the winger broke into a gallop. The whole rearguard was rather befuddled, an accident waiting to happen.

Chelsea should have run riot early. Within 100 seconds of the start, Oscar had clipped Diego Costa clear to test that suspect hamstring as the Brazilian-born forward eased into space between the centre-backs and down on goal only for Rui Patricio to bring off a fine reaction save with his legs when it seemed easier for the striker to score.

Thereafter Andre Schürrle, sprightly yet profligate and unrewarded the previous week against Bolton, should have rattled up a hat-trick only for anxiety to grip each time he attempted a finish. He was most culpable when steering Hazard’s pull-back wide of the far post midway through with the goal at his mercy and Rui Patrício resigned to a concession. Mourinho, watching on in disbelief from his technical area, winced as the chance dribbled wide.

There was a vibrancy to Chelsea’s approach play, even if the home side rather invited each wave of attack with little pressure exerted to snuff out the visitors’ possession at source. In that context the only real surprise was that the lead would eventually come from a set piece. Andre Carrillo floored Hazard again and Fabregas clipped his free-kick early while Sporting dawdled. Nemanja Matic, a former Benfica player and heckled throughout, was unmarked beyond the far post to arc a well-placed header over Rui Patricio and into the net to earn the lead the visitors’ dominance had long since merited.

So disorganised had Marco Silva’s young team been that some in their number appeared to realise the free-kick had been taken and the chance converted only once the travelling support at the opposite end of the Alvalade stirred. They had been just as ineffective as an attacking force, an isolated Islam Slimani heading Jonathan Silva’s cross down into the ground for Thibaut Courtois to claim from their clearest sight of goal.

The homeside needed to regroup, pray some complacency undermined their opponents and hope to capitalise on the reality that their deficit somehow remained so slender.

They were more urgent thereafter, Nani's pace testing Branislav Ivanovic – even if the Serb treated plenty of his darts with disdain – but he buried a shot into the side-netting and his side remained a jumble of isolated bodies at the back.

Chelsea’s counters were rapid, often with players liberated on the halfway line only for desperate late challenges to save the day. Oscar again found himself alone in enemy territory but Rui Patricio thwarted his shot with Schürrle pleading for a square pass at the Brazilian’s side.

They even broke from potentially dangerous Sporting free-kicks on the edge of Courtois’s area. Yet with each miss the fear grew that, when the hosts did build up a spell of momentum, it might yield barely credible parity.