Boro were without a handful of first-team players against the non-league outfit, yet Neil Warnock was still able to name a strong side for the fixture.
Former Bristol City forward Jamie Paterson, who is on trial at the club, started his second friendly match for Boro after playing in the 2-1 win over Plymouth last week.
Defender Sol Bamba, who has also been training with Boro, came off the bench in the second half when the Teessiders made wholesale changes just after the hour mark.
Things appeared to be going to plan for the visitors when Dael Fry headed them ahead inside six minutes, yet goals from York duo Mackenzie Heaney and Mark Beck before half-time turned the game on its head.
Here’s how each Boro player fared.
5. Dael Fry - 6
Scored a towering header from a free-kick, yet his short clearance led to York’s equaliser. 6 Photo: Getty Images
6. Djed Spence - 6
Started as a left wing-back. Improved in the closing stages and delivered a couple of inviting crosses into the box after switching to the right. 6 Photo: Stu Forster
7. Sam Morsy - 6
Made Boro tick in the early stages when he looked to get on the ball and move it quickly. Committed some needless fouls as the game wore on though. 6 Photo: Catherine Ivill
8. Jonny Howson - 5
Made his first appearance of pre-season after recovering from injury and still appeared to be getting up to speed. 5 Photo: Stu Forster