it was a pointless sub, its not even like they have/had any games midweek in the coming period or in the last couple of weeks, they play once a week and Dzeko is like the least workrateish striker on the planet, so chances of him ever being tired are exactly zero. if anything, he should have subbed out some of the more working players like Nainggolan (maybe he did, no idea as i didnt watch the game). but you can clearly see it means a lot for Dzeko to finish as top scorer, and making your best striker dissatisfied like this was a stupid move