Of course you know that in close games the situation is different. A starter (set also for back up and reserve) will never get random subbed in a close game.
In blowouts, it happens sometimes. In my experience, the primary reason for this might be stamina. If player's stamina is too low, he will occasionally (if not often) get random subbed in a blowout. I am almost sure that Bošnjak and Šupić have stamina less than 7. Please correct me if I'm wrong.
yeah, my whole team is pretty low with stamina...
but there is no time to train stamina right now, only if one of my trainee get injury...
still, I am not sure that low stamina is the only reason for random subs in last minutes...
I was u21 coach for 6 seasons, and I supervise training for many u21 players with low stamina...
if they play in lower division, or if they are the best players in a team, there is no problem to get 48+ every week, even in blowout games...