Seamus Coleman's face when he left the pitch indicated the severity of the reckless challenge he had just suffered. The Republic of Ireland captain was taken off on a stretcher, while Neil Taylor was sent off for Wales.
However, it could just as easily have been Gareth Bale sent off. Just a minute before, the Real Madrid man was booked for a terribly-timed late sliding tackle in the Ireland area. The booking means he will miss Wales' next qualifier against Serbia, and will be a huge loss to Chris Coleman's side.
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After a slow start where Bale sported short sleeves and gloves in a relatively humid night in Dublin, the Madrid man grew into the game. In the early stages Burnley full-back Stephen Ward had the better of him, dispossessing him twice and forcing the 27-year-old into unexpected mistakes.
Half in hour in, the gloves came off, literally and figuratively as Bale warmed into the match. He moved inside and began to dictate the game, showing why he was once the world's most expensive player. Just after the restart, he tested Darren Randolph with the game's first shot on target before going agonisingly close with an effort that went just wide of the post.
Just when it looked like Wales had the upper hand on the game, disaster struck in two crazy minutes. First, Bale went in late on John O'Shea, catching the Sunderland defender just below the knee, and then Taylor injured Coleman with a similar horror challenge.
With the extra man, Ireland started to dominate proceedings, but Bale always looked dangerous. Both with and without the ball. The attacker easily could have picked up a second yellow card for a high boot on the energetic James McClean, and then seconds later went close to scoring once more after a tremendous run through the Irish middle.
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In a game where both managers had discussed the merits of a draw beforehand, neither could take advantage. The result suits Ireland better, with the Boys in Green level with Serbia at the top of the table. Wales are now four points behind the leaders, and with Bale suspended against Wales, now face a steep challenge to reach the 2018 World Cup.
Paradoxical Bale could have been Wales' hero, but instead he is one of their villains, leaving them with little chance of qualifying and ensuring the highs of Euro 2016 are unlikely to be repeated.