Debut caps off 'never forget' night for Roo new boys
The pair – along with Aston Villa’s Chris Herd – made the senior international debuts in the tough 2-0 loss in Liege.
Sainsbury, who is having a superb season with PEC Zwolle in Holland, started in the heart of defence and despite a shaky start was one of the Socceroos' best.
“I was lying in my bed before the match and I was just giggling," an ecstatic Sainsbury told Fox Sports.
"I couldn’t believe I was at this stage.
“Six months ago I was out with a fractured knee and I was devastated but to come back and finally get rewarded with a jersey is incredible.
“I was expecting something special but that was just unreal. The pace and the power and speed of the guys was unbelievable. It really opened my eyes.”
The 22-year-old was reunited with ex-Central Coast teammate, Alex Wilkinson, at the back and the pair’s combination – with former Mariners goalkeeper Mat Ryan as well – stood up under some intense pressure from the hosts.
“We’ve got the bond over the years so we knew a few things that were going to happen between us,” Sainsbury said.
“But at the same time I was really just trying to get to grips with the game at the start because I’ve never experienced anything like that in my life. It was incredible.
“Even though they had some of their bigger names out, the list and the clubs they play for, I was definitely pinching myself to start alongside one of my old partners, it was definitely a good experience.”
Smith only found out a few hours before kick-off he was eligible to play after finally receiving his international clearance.
The Liverpool-loanee replaced Tim Cahill with 20 minutes left and looked assured playing on the left-wing.
“It was a dream come true for me and my family,” Smith said.
“It means a lot to me. I was told this morning that it (clearance) didn’t come through then later found out it did and all the players and staff cheered for me and it was really good.
“They (Belgium) are a good side obviously but I thought we did pretty well.”