Michael Phelps was hilariously unfazed as an opponent danced in front of him before a race

NBC

Michael Phelps advanced to the 200m butterfly Olympic final on Monday night from Rio, but the real drama of the evening came in the dressing room during a rare face-off between Phelps and South African swimmer Chad Le Clos.

Le Clos, remember, narrowly beat Phelps for the gold medal in the same event at the London Olympics in 2012. As the two waited in the dressing room prior to their semifinal on Monday night, LeClos started shadow-boxing, jumping in place, and making a small scene.

Phelps, sitting right next to him, gave him an absolute death stare.

NBC

Phelps certainly did not approve of Le Clos' routine. He looked straight-up mad, and at one point even seemed to roll his eyes.

NBC

Look at that face!

In the ensuing semifinal, Phelps finished second and Le Clos, third. 

"That was a bit of an angry swim," NBC commentator Rowdy Gaines said afterwards of Phelps.

Michelle Tafoya, then, asked Phelps what he thought of Le Clos' pre-race routine. Phelps, who had just advanced to his fifth Olympic final in the 200m butterfly, sounded unperturbed. 

"He does his thing, I do mine."

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