Those two have a history, so it was pretty clear that Syndergaard was trying to hit Utley. There's no place for that in sports, regardless of what some baseball fans, players, coaches, etc. believe. For whatever reason, baseball culture has perpetuated this type of childish behavior, but it only hurts your team. If he had wanted to get back at Utley, he should have tried to strike him out.
Regardless of the history between the two teams, the rules in sports are in place for a reason. When the actions of one player directly threaten the safety or well-being of another, it is the umpire's job to respond to what he sees and make a judgement call about the action to take. In this case, the umpire could have either warned or ejected, as per the rules, so the choice to toss him from the game was absolutely justified.
Umpire needed to give him a warning. This was the FOX game of the week. You've got Kershaw going tomorrow and he's going to get the same treatment. Anything close to being outside the lines and now they have to toss him. Just bad for MLB. You throw behind a guy you get an in game warning. You hit em or throw behind him again and your gone. Ump trying to be bigger than the game.
It is hard to tell if something was intentional or not until you investigate it further. In the middle of a game is not the proper time to investigate something. Sometimes stuff just happens without the person realizing they are doing it. Let them play the game and investigate later. That is what they make astrics for.