Giggs was assistant manager at Manchester United when Rashford was handed his debut as an 18-year-old in a 2016 Europa League tie against Danish club Midtjylland.
Rashford scored twice after replacing Anthony Martial, who had been injured in the warm-up, and has gone on to star for United and England — and Giggs insists he is keen to give youngsters opportunities on his Wales watch.
“It has never been a problem for me giving young players a chance,” Giggs said ahead of his opening games at the China Cup this week.
“Even in my four games at United (when he was interim manager in 2014) I gave Tom Lawrence and James Wilson their debuts. I am not afraid to do that.
“Marcus was obviously someone I had seen develop and he got his chance with an injury in the warm-up.
“When I got my chance it was Lee Sharpe who got injured. I couldn’t see a way into the first team. Sharpey had won PFA young player of the year and he was playing for England.
“I was thinking ‘he is in my position’, but it is up to young players to take their chance.”
Giggs makes his bow as Wales manager at the China Cup, a four-team tournament being played in the southern Chinese city of Nanning.
Wales play the hosts on Thursday before being involved in either a third-place game or a final against the Czech Republic or Uruguay the following Monday.
Injury and illness has deprived him of the services of Chelsea midfielder Ethan Ampadu and Sheffield United striker David Brooks, who both made their debuts against France in November.
But Swansea defender Connor Roberts, Brentford midfielder Chris Mepham, and Preston striker Billy Bodin are in the squad for the first time.
“Young players can give you inspiration,” Giggs said.
“All of a sudden you go from getting a little bit of time on the ball to having to up your game.
“You can’t take two or three touches because they are on you, they are aggressive and you are looking over your shoulder.
“You’re suddenly thinking ‘he is after my position’ so you need to raise your game.
“That is what I want to emulate, that competitiveness in training we had at Manchester United.”