McCrorie is part of the Rangers first team at the moment and has played against Old Firm rivals Celtic this season.
The 19-year-old defender is still very raw and is developing, but the youngster has a lot of potential and talent.
Rangers midfielder Holt, 24, has praised the Scotland Under-21 international and his Ibrox teammate.
“I’ve been really impressed with all the boys in the under-20s who have come up to train with us,” Holt told Rangers’ official website.
“They are training with us on a more regular basis, and as you saw, Ross McCrorie got his chance and did really well.
“I was delighted for him as he deserved it, and all the boys who have come up have done really well.
“Like I said earlier, there are going to be opportunities through the season where people drop out the team, and someone needs to step-up and take that opportunity.
“Ross did that, and I think it shows the rest of the younger lads and the 20s there’s an opportunity there.”
Rangers finished third in the Scottish Premiership last season and are aiming to end up at least in second place in the league table during the 2017-18 campaign.
The Gers’ performances and results so far this season have been mixed, but Pedro Caixinha's side can still clinch the runners-up spot.
The Ibrox outfit are third in the Scottish Premiership table at the moment with 14 points from eight matches, six points behind Celtic and Aberdeen, who are first and second respectively in the standings.