Grant Hanley, Jacob Brown and Jon McLaughlin withdraw for Scotland

Scotland Under-21 cap Robby McCrorie has previously been involved with the senior squad

Grant Hanley, Jacob Brown and Jon McLaughlin have withdrawn from Scotland's squad before Wednesday's Nations League match with Ukraine.

Robby McCrorie has been called up to replace fellow Rangers goalkeeper McLaughlin, who has missed his club's past two games.

Forward Brown missed Stoke's weekend draw with QPR, but Hanley played in Norwich's draw with West Brom.

The defender had started Scotland's past two Nations League games.

After Wednesday's match at Hampden, Scotland host Republic of Ireland on Saturday and face Ukraine in Poland next Tuesday.

Captain Andy Robertson was not named in the squad after Liverpool manager Jurgen Klopp revealed the left-back would not be fit until October.

After beating Armenia home and away, Steve Clarke's side currently sit second in Group B1, one point behind Ukraine and two points in front of the Irish despite being humbled 3-0 in Dublin in June.

Craig Gordon, who is confident of shaking off a knee knock, feels Scotland are much better prepared physically and mentally this time.

"It was a disappointing camp all round last time and we need to do better - we know that," the Heart of Midlothian goalkeeper said.

"It's a different stage of the season. Hopefully we have got a lot more players who are in a better frame of mind, better condition, than we were at the end of last season.

"There were a lot of tired players trying to grind it out at a difficult stage of the season. A lot of players had played 50-60 games already leading up to that and it's impossible to keep going at the very highest level when you have to play that amount of games.

"You had a lot of players who had had a lot of disappointments towards the end of the season, missing out on Champions League, top-four qualification, whatever it may be. It was very difficult then to lift it to go again."

Scotland squad

Goalkeepers: Craig Gordon (Heart of Midlothian), Liam Kelly (Motherwell), Robby McCrorie (Rangers)

Defenders: Jack Hendry (Cremonese), Aaron Hickey (Brentford), Scott McKenna (Nottingham Forest), Nathan Patterson (Everton), Ryan Porteous (Hibernian), Anthony Ralston (Celtic), Greg Taylor (Celtic), Kieran Tierney (Arsenal)

Midfielders: Stuart Armstrong (Southampton), Billy Gilmour (Brighton & Hove Albion), Ryan Jack (Rangers), John McGinn (Aston Villa), Callum McGregor (Celtic), Kenny McLean (Norwich City), Scott McTominay (Manchester United), David Turnbull (Celtic)

Forwards: Che Adams (Southampton), Ryan Christie (Bournemouth), Lyndon Dykes (Queens Park Rangrs), Ryan Fraser (Newcastle United)