The 23-year-old Celtic defender and Scott McKenna headed home their first Scotland goals in a match totally dominated by Steve Clarke’s much-changed side.
Ralston, replacing former Hearts defender Aaron Hickey in his first start for the national team, was a stand-out performer at right wing back along with John McGinn in midfield as the Scots carved open their opponents at will.
It was Scotland’s first meeting with Armenia, but they will face them again in Yerevan next week after a trip to Dublin this weekend to take on the Republic of Ireland.
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Those two fixtures will surely be much tougher assignments than this one, Scotland controlling the first half and staying on the front foot in the second. They created plenty of chances to lift the Tartan Army after last week’s disappointing World Cup exit. The only thing that was missing from an accomplish performance was more goals.
McGinn, an energetic presence in the middle of the pitch who always wanted the ball, had about half a dozen efforts, the the best of them crashing off the underside of the bar. The goal he deserved did not arrive, but the former Hibs midfielder’s contribution was immense. At the other end of the pitch, Hearts goalkeeper Craig Gordon was a spectator for the most part, recording one of the easiest clean sheets of his Scotland career.
This was a game Scotland simply had to win, kickstarting a new campaign which could well provide Scotland’s best route through to the next major tournament, Euro 2024.
Armenia are a lowly 92nd in the world rankings, 53 places below Scotland in 39th, but had shown that they are capable of causing an upset in the Nations League by beating Republic of Ireland 1-0 in their opener last weekend.
It was hailed as "one of the greatest victories" in Armenia's history by 66-year-old head coach Joaquin Caparros, who had presided over a humiliating 9-0 capitulation to Norway in Oslo in their previous outing.
Clarke, of course, was never going to take them lightly in what was the first meeting between the nations. Nevertheless, the Scotland boss made six changes to his team after the disappointing World Cup play-off exit at the hands of Ukraine.
John Souttar, Jack Hendry and McKenna formed a brand new back three, reflecting the poor defensive display seven days earlier at the national stadium when Scotland’s World Cup dream was shattered.
Ralston came in for Aaron Hickey at wing-back, with Stuart Armstrong and Ryan Christie also coming in as attacking midfielders in support of lone striker Che Adams.
The new boys were eager to impress from the off. Ralston, Scotland’s best player on the night, zipped two low crosses across the six-yard box inside the opening eight minutes. At least one of them should have been converted. But Armstrong clipped the post with the first. Andy Robertson fired wide with the second.
Armenia looked every bit like a team ranked 92nd in the world who had been scudded 9-0 in their last away match. Defending deep and in numbers, they were still not able prevent Scotland from slicing them open with ease and looked like they would concede every time a cross was delivered into their box.
Hendry should have scored from a free header before Raltson charged into the box with a superb run from to get on the end of Armstrong’s delicious cross at the back post. He nodded back across goal to put Scotland in front on 27 minutes. The floodgates appearing to be open, McKenna showed strength and determination to head home the second from McGinn’s corner before half time.
It was the Nottingham Forest centre-back’s first Scotland goal on his 25th appearance and he thought he had bagged a second just a few minutes later, only to be denied by VAR, his effort ruled out for offside after another cross that the Armenians could not deal with.
The lead could and should have been greater at the break, Scotland having enjoyed 71% possession and Armenia rarely getting out of their own half.
Caparros made three halt-time changes, throwing a second striker on in a bid to get further up the pitch. But it made not a jot of difference.
It was easy to see why Armenia have found goals hard to come by on their travels, netting just once in the five away games they had played before arriving at Hampden.
Souttar did have to stay on his feet and make a last-ditch tackle inside his box when left exposed one-on-one after a slip by Hendry, and Gordon was forced to make a routine save low to his right on the hour. But that was all the visitors could muster in terms of a goal threat.
Some comical defending between goalkeeper and defender almost let Adams in for the third and the Southhampton striker’s next attempt from just eight yards was blocked by a wall of defender.
With rain lashing down McGinn crashed an effort off the underside of the bar and had whipped another clean strike just inches over the bar.
Hickey was handed 15 minutes in his favoured left-back position, the former Hearts defender having had a rather uncomfortable evening when starting on the right seven days earlier.
Sunderland Ross Stewart was also given his debut from the bench, but had little time to make an impression.
By then, the job had been done.
Scotland (3-4-2-1): Gordon; Souttar, Hendry, McKenna; Ralston (Patterson 76), McGinn, McGregor, Robertson (Hickey 76); Armstrong (McTominay 76), Christie (Stewart 87); Adams (Brown 87). Subs: Clark, Kelly, Hanley, Gilmour, Cooper, Turnbull, Campbell.
Armenia (4-4-1-1): Yurmenko; Hambartsumyan, Haroyan, Mkoyan, Arman Hovhannisyan; Kamo Hovhannisyan (Voskanyan 45), Grigoryan (Wbeymar Angulo 45), Spertsyan (Udo 71), Barseghyan; Bayramyan (Dashyan 88); Adamyan (Bichakhchyanat 45). Subs: Avagyan, Buchnev, Babayan, Harutyunyan, Margaryan, Rudik Mkrtchyan, Styopa Mkrtchyan.
Referee: Sebastian Gishamer (Austria)