It's been a while since Ottawa Senators captain Brady Tkachuk dropped the gloves in a regular season tilt. The one he had on Tuesday night in Buffalo, his first since January, didn't work out very well.

Tkachuk stood up for Tim Stutzle after he took a hard hit from Buffalo Sabres forward Jordan Greenway. Tkachuk and Greenway were teammates at Boston University in 2017-18 and it seemed like a standard bout between two willing parties – nothing to see here.

But instead, the fight caused plenty of social media debate over what it means to be an instigator.

Tkachuk obviously wanted retribution, but he also gave Greenway plenty of time to agree to the fight. He could have skated away if he didn't want it. And Greenway even dropped his gloves first.

And yet, the officials handed Tkachuk the extra penalty for being the instigator. It was a crucial decision in the game and Travis Green wasn't happy. Despite having the game's worst power play, the Sabres quickly made it 1-0, scoring with the extra man.

So let's hit the rule book.

Here's NHL Rule 46.11: Instigator - An instigator of an altercation shall be a player who by his actions or demeanor demonstrates any/some of the following criteria:

• distance traveled;

• gloves off first;

• first punch thrown;

• menacing attitude or posture;

• verbal instigation or threats;

• conduct in retaliation to a prior game (or season) incident;

• obvious retribution for a previous incident in the game or season.

Tkachuk checked some of the boxes and so did Greenway. There was absolutely zero reason to give either guy an instigator. Every referee seems to have his own interpretation of the rule book.

It wasn't the sole reason Ottawa lost. They ended up playing a really bad hockey game after that. But the call handed the Sabres easy momentum, getting a brutal power play going, and feeling good about themselves after a three-game losing slide.

The Sabres went on to a 5-1 win over the Senators, an appropriate result. The Sens are 5-1 at home and 1-5 on the road.