Goals from Abdallah Sima (x2), Nicolas Raskin and Cyriel Dessers sealed the points for the home side in what was a disappointing afternoon in Glasgow.
Speaking to Hibs TV after the match, the Hibs defender shared his thoughts on a frustrating 90 minutes.
“It was a very disappointing afternoon. I thought we stuck to our gameplan as best as possible, but we made too many mistakes defensively which ultimately cost us.
“They used the ball more effectively than we did, especially in the final third. When we did break their press we either made a sloppy mistake or gave the ball away.
"Things like that happen, but we did stick to our gameplan which is something the Manager was keen for us to do.
“The goal before half-time was a sucker punch but there are no excuses for some of the goals that we conceded today.”
The result brought to an end a six-match unbeaten run for the Hibees, and with a busy period of fixtures in the next few weeks - including home fixtures against Celtic, Ross County and a Viaplay Cup Semi-Final at Hampden - Fish stressed the importance of learning from the defeat and bouncing back quickly.
“These results happen, we need to reset and go again because we have a big few weeks ahead of us.
“We have a big three weeks up ahead, but these are the games you want to be playing and challenging ourselves week in, week out.
“We know if we keep sticking to our gameplan and playing the way the Manager wants us to then I am sure we will be alright.”
