The last game of Matchday 1 at the 2018 World Cup offered up the most bizarre goal of the tournament thus far. And it was controversial, too. But it shouldn’t have been.

Senegal doubled its lead vs. Poland midway through the second half when M’Baye Niang capitalized on Polish confusion, intercepted a back-pass and tapped the ball into an empty net:

At first glance, it was simply the result of miscommunication between Polish defender and goalkeeper. But replays painted the goal in a different light.

The goalscorer, Niang, had been off the field injured. Seconds before the back-pass, he had re-entered the pitch at midfield with the referee’s permission. He almost immediately ran onto the errant pass from Poland’s Grzegorz Krychowiak, intercepted it and sped past Poland keeper Wojciech Szczesny.

So the question is: Should the referee have allowed Niang back onto the field in that moment? Did his decision give Senegal an unfair advantage?

Poland complained that it did. But there was no way to review the play. And it was tough to fault the referee, given that the ball was all the way back in Senegal’s end when he gave Niang the signal.

Senegal ultimately won the match 2-1.

Was the referee at fault?

There is no specific protocol in the relevant section of the rulebook for when a ref should or shouldn’t allow an injured player to re-enter the field. The IFAB laws of the game simply state, “If the ball is in play, re-entry must be from the touchline [sideline].”

So no, the referee wasn’t at fault. It was merely an unfortunate – or, from Senegal’s perspective, fortunate – coincidence.

Fox Sports rules expert Joe Machnik said after the game that “the referee could have waited until the ball was in a neutral zone, where no team was in the attack” … but that’s exactly what the ref did. He waved Niang back on well before the back-pass, when the ball was in neither team’s possession.

How was the ref supposed to know that the next two actions would be a clearing header and a long, looping back-pass?

The idea – albeit not codified in the laws of the game – is to time the signal so that the returning player doesn’t gain an advantage. In most cases, that means bringing the player back onto the field away from the play, so that he A) can’t immediately intercept a pass or put pressure on the ball, or B) can’t immediately make himself available for a pass. Niang fit neither of those descriptions.

So the goal was perfectly legal. Nobody was at fault except for Polish players.

Should the rules be changed?

They probably should be. And there’s actually a decent chance they will be specifically because of this controversy. High-profile incidents often lead to rule tweaks, and this could be one of those cases.

A reasonable fix would be to specify that an injured player must wait for another stoppage in play to re-enter the game. That would serve two purposes: It would prevent situations like Tuesday’s. It would also dissuade players from exaggerating injuries and crumpling to the field, as often happens late in games.

So don’t be surprised if FIFA and IFAB make that change.

But again, that doesn’t mean anything was wrong with Niang’s goal for Senegal.

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Henry Bushnell covers global soccer for Yahoo Sports. Have a tip? Question? Comment? Email him at henrydbushnell@gmail.com, or follow him on Twitter @HenryBushnell, and on Facebook.

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