Mistakes, flat back four and GMS tricks ....

Courier Sport looks at five things we learned from the friendly.

Alex McLeish remains defiant

The Scotland manager has now lost six of his eight matches in charge since returning to the role, but he spoke of his determination to overcome a difficult start. However, the two Nations League games against Albania and Israel next month are crucial to his future. Failure to seal top spot and a guaranteed Euro 2020 play-off could signal the end for him.

Scotland need to cut out the mistakes

Just like the recent 4-0 defeat by Belgium, Scotland undid some decent work by gifting soft goals. A lack of awareness from full-backs Stephen O’Donnell and Andy Robertson contributed to Helder Costa’s opener, Portugal went two ahead when Eder had a free header from a simple freekick, and Bruma netted on a clinical break after Jack Hendry lost possession as he took the ball out of defence.

Scotland looked more comfortable with a flat back four

Much has been made of McLeish’s penchant for playing 3-5-2, a formation that allows Celtic’s Kieran Tierney and Liverpool’s Andy Robertson to start, albeit neither play in their natural left-back position. Tierney’s absence through fatigue allowed McLeish to go to a 4-2-3-1 formation – which they played under predecessor Gordon Strachan – and the Scots certainly looked more comfortable than they did in Thursday’s 2-1 defeat by Israel. However, they excelled in a 3-5-2 against Albania last month.

Gary Mackay-Steven can use his tricks on the international stage

The Aberdeen winger had only played six minutes for Scotland, almost five years ago, before coming off the bench in the 76th minute. He made his mark in his latest brief cameo as his brilliant back-heel set up Steven Naismith’s goal.

Scotland need Stuart Armstrong to start playing more regularly

The Southampton midfielder produced an impressive first-half display after being left out in Israel and still had the burst of pace that can drive him past opponents. But his lack of game time appeared to tell after the break. He received treatment for tight calf muscles before eventually going off with 13 minutes left. A sharp Armstrong is a major asset to Scotland but he has only played 120 minutes in the Premier League since his summer move from Celtic.