But he admitted striker Che Adams faces a race against time to be fit for the clash with top seeds Spain on Tuesday after he was forced off in the second half of the 3-0 win over Cyprus with a tight calf following a challenge by St Mirren's Alex Gogic. Clarke rated the Southampton striker's chances at an "optimistic 50-50".

Two late goals from substitute Scott McTominay gave the scoreline a more commanding look after John McGinn’s opening goal – his 16th for Scotland – had given the hosts a deserved lead in front of a sell-out crowd. They toiled at times to build on this start and the first of McTominay’s strikes settled the nerves of the fans after Cyprus manager Temuri Ketsbaia’s switch of formation saw the hosts start pushing for an equaliser.

“It’s a good start to the group with three points,” said Clarke. “There were some good things and other bits we need to get better at. But overall, it was very pleasing. It’s nice to start the campaign with what looks like a comprehensive home win with a 3-0 scoreline. Let’s look at the positives. In the first 30 minutes, I thought we were outstanding.

Steve Clarke celebrates during Scotland's 3-0 win over Cyprus.

“The rotations and movement on both sides was really good. (Andy) Robertson and (Aaron) Hickey were getting forward, (Kieran) Tierney and (Ryan) Porteous were stepping in from the back. (Stuart) Armstrong was picking up good positions and running with the ball. I thought we were really good for half an hour. But then I just felt we got a little bit sloppy and casual.”

Clarke praised the impact of substitutes Lyndon Dykes, Ryan Christie and McTominay, who all played a part in the second goal with four minutes left. But there is real concern over Adams, who Dykes replaced. “He just felt his calf tighten a little bit before he came off,” reported Clarke. “We’ll assess him and see how he is. It’s far too early to decide whether he’s going to be in or out. It’s obviously a short turnaround to the next game so if it’s 50-50 that would be optimistic, to be honest. If somebody comes off with a tight calf you’re not too sure what’s going to happen.”

Clarke at least has goal power in the form of McGinn. All his international strikes have come under the manager’s charge. “It looks like a good decision to push him a little bit further forward!” said Clarke. “If I take any credit, that’s the only thing I did right. No, it’s down to John. He arrives late in box really well and his finishing is normally really clean. It looks like an easy goal he scored but he still had to have the technique to put it in. That’s now 16 goals he’s scored and for a midfield player - even though I use him as an attacking midfield player - is a great return. He’s also had six assists so it’s a big contribution to what we’re trying to do.”

Clarke was happy with Angus Gunn’s debut in goal after he told the ‘keeper he had won the race to start on the morning of the game. “The only thing I said to him at half-time was ‘check your studs,’ because he had that little slip that had everybody a little bit nervous than it should have done,’ he said. “But thankfully he sat on the ball. But for a goalkeeper to get his first cap and play and get a clean sheet with no mistakes, it’s good.”

Steve Clarke hails 'very pleasing' Scotland win but concerns arise over Che Adams injury