With 29 minutes showing on the big screen at one end, behind the running track, Wales were 2-0 up and seemingly coasting to victory in Iceland but just as Craig Bellamy was beginning to make this coaching lark all look rather straightforward, a concerning second-half collapse proved there is still plenty of room for improvement.

Nevertheless, three games into his management career, Bellamy was enthused, determined to strike an upbeat tone and there were also ­reasons to be cheerful for the ­travelling supporters, a couple of whom went down to their underwear despite sub-zero temperatures.

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Brennan Johnson nudged in on the goalline to score his seventh goal in seven games before Harry Wilson doubled Wales’s lead, but after the break Iceland asked questions of Bellamy’s side and the reality is they wilted rather feebly under pressure in trying to find the answers. “They were there, but it is about being able to find them at the time,” Bellamy said afterwards.

“There is a lot to benefit from it for us. It allows us to coach more and put a library in the players’ heads. ‘Remember this situation? Remember when we found this period difficult.’ In the long run, I’m really happy. This is not me trying to sugarcoat drawing from being two-nil up, this is what I said to the players.”

Logi Tómasson, a half-time ­substitute, was the architect of ­Iceland’s two goals in three second-half minutes that drew parity and Jón Dagur Thorsteinsson almost ­completed the comeback but his curled shot cannoned off a post with a minute of normal time remaining.

“Football is a crazy sport ­sometimes,” said Åge Hareide, the Iceland manager who previously coached Denmark and Norway, his homeland. “I have to praise the team that we lifted ourselves and came back in the second half and played really good football. We should have won it, and that is the only disappointment at the end.”

Wales made a lightning-fast start in victory in Montenegro last month, scoring twice in the opening three minutes, and here, while they had to wait a little longer, they were two up before the half-hour mark. Neco Williams, who had a flawless first half but for taking a boot from the Preston midfielder Stefán Thordarson in the anatomy, set up both goals with identical pinged passes over the Iceland back line.

First, Wilson saw his shot ­scrambled clear on the line by the Brentford goalkeeper Hákon Rafn Valdimarsson before Johnson feasted on the loose ball to continue his extraordinary goalscoring run, and second time around Wilson buried a bouncing ball into the bottom corner.

Wilson saw another effort take a wicked deflection and rebound against the foot of a post and a few minutes before the interval the Fulham midfielder sent Sorba Thomas through on goal with an incisive pass, but Thomas prodded the ball at the Iceland goalkeeper.

Jóhann Berg Gudmundsson, the Iceland captain who played under Bellamy while the Wales manager was assistant to Vincent Kompany at Burnley, wellied a free-kick on to the roof of Danny Ward’s net but Wales had kept the hosts at arm’s length – for the first 46 minutes. Williams cleared off the line and Bellamy’s name filled the Icelandic air.

The second half, with ­Johnson withdrawn at the interval as a ­precaution, was a chore for Wales, who could feasibly have trailed 3-2 10 minutes after the restart. Mikael Ellertsson, a half-time arrival, fired wide four minutes after the break and a minute later Orri Óskarsson shot against the crossbar. Ellertsson then had another chance, shovelling over after Andri ­Gudjohnsen, son of Eidur, plucked Thorsteinsson’s pass out of the sky. Ward then saved from Gudjohnsen.

Iceland were a different ­prospect now and moments after Ward saved superbly from ­Gudmundsson and from the subsequent corner ­Tómasson sent an immaculate left-foot shot with the outside of his boot into the far corner.

Wales failed to heed the ­warnings. Thorsteinsson freed Tómasson down the left flank with a neat backheel and the latter made light work of­bypassing Connor Roberts and moseyed to the byline. Tómasson attempted to square the ball and his cutback cannoned off Ward and in.

Gudjohnsen flashed a shot wide in search of a third and then ­Thorsteinsson cut inside and struck a post. For Wales, in stunning ­scenery, this really was both beautiful and ugly.