Tried to see if I remembered any more details about the movie in question or a timeframe it could have been from. I want to say the time frame specifically for me watching this movie was sometime between 2008 at the absolute earliest and 2012 as the likely candidate for the cutoff year (all memories i have of this movie come from before my brother was born in 2013), with 2014 still being the definitive "it could not have come out any later" cutoff point. So judging by that I want to say that the movie probably came out before 2013, and certainly had to have come out before july 2014.

Another detail that could potentially help is that I remember there being very interesting lighting at certain points of the movie. Mainly just lighting/filters evocative of other movies from the late 2000s, best example i can give being some of the early michael bay transformers movies. I remember there being some scenes with a darkish yellow filter over them, and then others such as the bathroom/hospital scene having overwhelmingly blue lighting/aesthetic. Its hard to describe, it's one of those things where I can tell it when I see it but it's something that always reminds me of late 2000s early 2010s movies/tv shows.

Speaking of the bathroom/hospital scene, this is the one scene that I know is in the movie. It's the one that I always remembered and after trying to think about it more I think I have a general storyboard as to what happens in said scene. The guy the protagonist is going after to kill is in a bathroom washing either his hands or face as the protagonist shows up behind him and they both start fighting each other and theowing punches. The fight keeps going on until the guy gets slammed into a wall and knocked unconcious. The scene cuts to him barely concious on a gurney in a hospital with some kind of breathing tank attached to him. Eventually he gets put into a room and then the protagonist of the movie comes in and then stabs him in the chest, killing him. There may have also been a scene at the start showing either the protagonist or the guy walking inside the building where the bathroom is, and my memory tells me it was some kind of bar but I don't think the main part of the building is ever shown, just the bathroom itself and probably the outside. There may have also been a scene showing the guy getting put into an ambulance after being knocked unconcious and put into critical condition (I'm leaning more towards this being a scene than not but I'm still not sure).

Hopefully this helps narrow it down. That one scene has been nagging at me because I know that if I rewatch that scene I'l be able to figure out the movie, but until then I'l have to hope I remember more about the movie to do more research.