Trailing 4-2 heading into the third period, the Los Angeles Kings wanted to get on the board early in the final frame. They did exactly that when a point shot from Matt Greene was tipped by Dwight King and by New York Rangers netminder Henrik Lundqvist to make it 4-3.
The goal was a controversial one, however, as there was a very good case for goaltender interference. As Lundqvist was trying to make the save, he had King inside his crease and impeding the goaltender from moving far enough to make the save.
It really depends on the angle you look at for the goal, but goaltender interference is not a reviewable play. That call has to be made on the ice to disallow the goal. It wasn't, despite pleas from Lundqvist and the Kings were a goal closer to making the comeback.
The only really telling angle is the above-net shot. Here's the GIF via @myregularface:
If King makes contact it's fairly minimal, but that isn't the important part. It's all about whether or not King's position impeded Lundqvist from making the save. It's also important to note whether or not Ryan McDonagh pushed King in on Lundqvist, thus negating interference. Based on the replay, it doesn't appear McDonagh was the reason King was where he was in the crease.
Since King tipped the shot immediately prior to making contact, the referees saw fit to negate any interference penalty, but that seems iffy at best.
Here's what Rule 69.1 says about goaltender interference:
This rule is based on the premise that an attacking player's position, whether inside or outside the crease, should not, by itself, determine whether a goal should be allowed or disallowed. In other words, goals scored while attacking players are standing in the crease may, in appropriate circumstances be allowed. Goals should be disallowed only if: (1) an attacking player, either by his positioning or by contact, impairs the goalkeeper's ability to move freely within his crease or defend his goal; or (2) an attacking player initiates intentional or deliberate contact with a goalkeeper, inside or outside of his goal crease. Incidental contact with a goalkeeper will be permitted, and resulting goals allowed, when such contact is initiated outside of the goal crease, provided the attacking player has made a reasonable effort to avoid such contact. The rule will be enforced exclusively in accordance with the on-ice judgment of the Referee(s), and not by means of video replay or review.
This is a judgment call by the officials, but the Rangers have a good argument the goal shouldn't have counted.
Later in the period, the Kings scored to tie the game 4-4. That call is going to loom largely in this series should the Kings take Game 2.