Tom English
BBC Scotland's chief sports writer at Hampden

Alex McLeish says he was likely to make changes to his side - and maybe his system - before losing five players from his squad after Thursday's defeat by Israel.

Blackburn Rovers' Charlie Mulgrew, who scored from a penalty in Haifa, Hearts' John Souttar, who was sent off before he was due to be replaced, and Celtic's Kieran Tierney, who scored an own goal, are all missing from the defence.

West Ham United's Robert Snodgrass and Manchester United's Scott McTominay, who did not feature, have also left.

Celtic midfielder Ryan Christie and Aberdeen duo Michael Devlin and Gary Mackay-Steven have been called in, but none of those start at Hampden.

It is the first time Devlin has been called into a Scotland squad, the 25-year-old who has made 11 appearances for this season after missing the entire 2017-18 campaign through injury and having joined Aberdeen from Hamilton Academical in January.

Mackay-Steven made his only full international appearance to date almost five years ago, when the 28-year-old came on for the last six minutes of a goalless friendly against the United States.

Christie played in the same midfield as Mackay-Steven while on loan to Aberdeen but has returned to Celtic this season and won three Scotland caps over the past year.

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Suggestions of disharmony in the Scotland camp followed Leigh Griffiths' decision to drop out of the squad to concentrate on his fitness after being left on the bench against Albania.

Scotland fans on social media are not too pleased with the decision to allow his Celtic team-mate, Kieran Tierney, to miss today's friendly because the defender was looking fatigued.

John@JSTurner17: "They can rest at the end of their careers. If you have the opportunity to play for your country and don’t fancy it cause you need a rest, you should be given a permanent rest and not selected again."

stand free and keep calm@crispybear1: "A rest! Is it not the.job they've trained for day in day out? As excuses go, it's pretty pathetic."

Andrew Leitch@andyl1981: "Footballers are so precious. All this needing a rest is absolute nonsense. Glasgow Tigers have two matches in one day today and Braehead Clan had three matches in three days. Toughen up and realise they aren’t working hard for a living."

Gary Donaldson@HarryChibber: "Sad state of affairs that. Griffiths quitting the squad made it easy for the rest of them. Should never be a choice to play for your country if you’re asked. We’ll never get to a tournament if that’s the attitude."

Allan Davidson@AllanDavidson7: "Relived to get a rest”? This is exactly the problem with our national team. Look at other small nations that are successful (Iceland). Those boys would run through brick walls just for the chance to wear the shirt. We don’t have enough guys like that at the right now."

Zach@OfficialZed: "Something clearly not right. Worrying."

Blair O'Connor on Facebook: "He's under pressure to pick Tierney, but the reality is there is no place for him in the team if Robertson is fit. He just needs to accept this."

Alex McLeish had said on Saturday he was not averse to ditching his back-three system - and the absence of the trio who started against Israel on Thursday made it easier for the head coach to revert to a back four this evening.

Charlie Mulgrew and John Souttar picked up injuries in Haifa and Kieran Tierney has been rested.

McLeish still believes that a back three, with Andy Robertson pushed forward into a wing-back role, is the best way to get his captain and fellow left-back Tierney into the team together.

But, with Tierney being excused duty, Robertson slots into his normal role, especially with the lack of fit central defenders left in the squad.

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Scotland head coach Alex McLeish has made six changes from the side that lost to Israel on Thursday.

Celtic's Craig Gordon replaces Allan McGregor, the Rangers man who was man of the match in Haifa, in goal.

Jack Hendry comes into central defence, where the Celtic man is joined by Aberdeen's Scott McKenna.

Stuart Armstrong comes into central midfield despite being out of the picture at Southampton, with his former Celtic team-mate, James Forrest, on the wing.

Swansea City striker Oli McBurnie starts up front along with Steven Naismith.

The formation allows captain Andy Robertson to move back to full-back from his more advanced role on the left.

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The good news for Scotland - not so much for ticket sales but for their chances of victory - is the absence of several top players from the Portugal squad.

Most notable of them all, of course, is superstar Juventus forward Cristiano Ronaldo, who is facing rape allegations his lawyer maintains are "completely fabricated".

Head coach Fernando Santos has also allowed Besiktas defender Pepe and Manchester City midfielder Bernardo Silva to leave the squad after Thursday's 3-2 Nations League win in Poland.

Winger Helder Costa, who has impressed for Wolverhampton Wanderers this season, could make his international debut in Glasgow.

Image source, Getty Images

The build-up to the game has already started on BBC Radio Scotland.

Expert analysis comes from former Scotland defenders Willie Miller and Stephen McManus, plus BBC Scotland's Tom English.

It's said of big clubs that you are always only one game away from a crisis and arguably that applies as much to international football.

The pressure that had been building for Alex McLeish after four defeats in five friendlies since he took charge in February eased considerably after an opening Nations League group win over Albania.

It was quickly heaped back on the Scotland head coach after a 2-1 defeat in their next League C, Group 1 match in Israel on Thursday that was more emphatic than the scoreline suggests.

A friendly against Portugal - the seventh best team in the world - is probably not the most timely of fixtures.

McLeish surely can't afford a repeat of last month's 4-0 drubbing by Belgium in Glasgow.

Stay with us for the build-up, live commentary and reaction from Hampden Park.

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