Scotland's case for the defence amid pitch invader and stingless Portuguese man o' awe

The head coach has refused to panic during Scotland's recent travails. While detractors will still point to a sequence of just one win in 16 games, this stalemate with Portugal is a step in the right direction. Wins at this level are hard to come by.

Amid green shoots of recovery after the Euros, Scotland had lost narrowly in their three previous assignments, including in Lisbon. Not this time. Cristiano Ronaldo and Co were kept out in a triumph for Scotland's back four. They withstood plenty of pressure, with centre-halves Grant Hanley and John Souttar impressive. If confidence is an issue within this current squad, they got a shot of it with this performance.

Two more Nations League matches remain, back in Glasgow against Croatia on November 15 before a trip to Poland three days later. Scotland are three points behind the Poles after their 3-3 draw with the Croats in Warsaw. Shorn of more than a dozen squad regulars in this international window, Clarke at least has some foundations to build upon. This was a performance of grit, organisation and determination against exalted opposition.

There were some statistical matters to record. Clarke clocked up his 62nd match in charge of the national team, moving him outright second in the standings, nine behind Craig Brown. Captain Andy Robertson now sits fourth in the list of all-time capped players on 78, with goalkeeper Craig Gordon now on 77. At the other end of the scale, Aberdeen right-back Nicky Devlin won his first cap as a late substitute.

With options limited in an inexperienced squad, Clarke only made one change to the team that fared well in Saturday's 2-1 defeat by Croatia. Striker Che Adams took Lyndon Dykes' place at the head of a 4-2-3-1 formation. Teenager winger Ben Doak started once again, a fourth cap for the mercurial 18-year-old, although this time he was on the left rather than the right. Clarke spoke pre-match of managing the hype surrounding Middlesbrough's on-loan Liverpool starlet, but there was little reason not to unleash him upon Portugal after some moments of promise in Zagreb.

A packed Hampden Park was also able witness a rare - and perhaps final - sight of Portugal's legendary 39-year-old forward Cristiano Ronaldo, only making his second appearance on Scottish soil. He was part of a Manchester United team that faced Celtic in 2008 and an unused substitute against Rangers at Ibrox in 2003

The only man older than him on the pitch was Gordon, whose last outing at the national stadium looked set to be a farewell against Finland just before the Euros. You would have got decent odds on the 41-year-old being back between the sticks at Hampden, although no doubt benefitting from No 1 keeper Angus Gunn's injury.

Gordon was afforded a warm reception by the Tartan Army, as was former first minister Alex Salmond, whose memory was marked with a minute's applause following his death at the weekend. Ronaldo's first touch was booed, before loud cheers greeted him giving the ball away.

Scotland started brightly, and really ought to have opened the scoring on five minutes. The ball was sent out to Doak and he found fellow Liverpool man Robertson. The left-back's cross was perfect, landing right on the head of Scott McTominay, but his effort was too close to Diogo Costa and the Portuguese keeper saved. It was a big moment, even so early in the encounter.

Portugal then assumed control of the football. Every one of their outfield players is a technician, comfortable in tight spaces and under pressure. Portugal did, however, pick up the first yellow card on 17 minutes, Diogo Jota cautioned for an over-the-top challenge on Anthony Ralston, before the moany Bruno Fernandes thumped the ball into the chest of Adams and Ronaldo got in the face of Belgian referee Lawrence Visser. Portuguese petulance was also on show.

Gordon was forced into a diving one-handed save from a vicious Nuno Mendes free-kick on 25 minutes and Ronaldo was back in the thick of it on the half-hour mark, sending a bicycle kick wide. Portugal's No 7 was the focus of their attacks, but Souttar and Hanley kept the closest of tabs on him. The Al-Nassr forward then blazed over from a promising position on 40 minutes. It was the last act of a fairly pedestrian first half.

It took two minutes into the second half for Ronaldo to be presented with another chance. Robertson gave the ball away cheaply and his Liverpool teammate Jota stood up a cross, only for the striker to head wildly over.

The quality level was diminishing. Portugal manager Roberto Martinez realised this. A trio of substitutes came on the hour-mark - including AC Milan's trickster Rafael Leao. But even he was muted. Portugal were labouring a little.

A rare Scotland attack on 71 minutes just broke down when Adams' downward header could not find McTominay in the box. Then substitute Ryan Gauld sent Ralston scampering down the right, his cross evading McTominay by a whisker. This was all against the general grain, Scotland were hemmed in, playing counter-attack football. It would be up to Portugal to conjure up a moment.

Ronaldo thought he'd had it on 82 minutes, but his driven effort skidded just wide. Unlike late on in the Estadio da Luz back in September, the Portuguese man o' awe had lost his sting.

His elder, Gordon, had the bigger say. What a cracking save he produced on 87 minutes, denying Fernandes from point-blank range. A pitch invader then scampered on, trying to get a selfie with Ronaldo. A steward rugby-tackled him, shortly followed by an excellent Devlin block on Leao. This was a night for Scotland's defence.