His eyes are always fixed on the ball.
As his opponent cocks and shoots, Nigel Tay anticipates the moment, generates a great deal of force, before lunging across goal to make a flying save.
Tay is the goalkeeper of the national men's water polo team, and his goal he protects measures 3m wide and 90cm high. Piece of cake, you say?
Now try staying afloat in the pool as you try to keep out shots that can reach 90kmh.
Or treading water - water polo players employ the egg-beater, where they alternate legs while frog-kicking - for 32 minutes.
Or tussling with another player trying to drag and climb over you as if he is trying to drown you.
On top of all that, the players have to stay alert, shutting out all the whistles and trash-talking, and try to launch counter-attacks.
Water polo was originally known as water rugby, and it is not difficult to see that it's effectively a combination of sprinting, basketball, ice hockey (in terms of the constant fouling), wrestling and rugby, all these in a pool that can measure up to 30m by 20m.
"Goalkeepers are all a little crazy, but more so for water polo goalkeepers," said Tay. "Our job is different from goalkeepers from other sports because we also have to deal with the water.
"So we need to do a lot of leg training, quick bursts and intense jumps because our game is basically that.
"The difficulty comes in how we sustain our jumps and our timing because we need to hang as high and long as we can to reach the extreme corners.
"There's also a lot of tactical fouling and grappling that go on under water. But what the referee doesn't see, he cannot award a foul. We just have to suck it up and stay focused."
Tay practises what he preaches - the 27-year-old actually tore his right adductor muscle in the third quarter of a crucial match against closest competitors Indonesia at the last South-east Asia (SEA) Games.
But he held on for the final quarter, where he made two point-blank saves to help his team win 8-5 en route to winning Singapore's 25th consecutive men's water polo gold.
There is no doubt Tay is a high-flier, but we are not just talking about how he overcomes water resistance to propel himself to make a vital save.
Outside of the pool, he is a doctor, and currently serves as a medical officer with the Singapore Armed Forces.
It is not an easy balancing act, as he said: "It is physically and mentally exhausting to juggle work and training because we have evening training every day.
"For me, it's about give and take. As a doctor, I have to make night calls and I'm thankful my coaches and team-mates are understanding when I have to miss training, but I do make-up training on my own."
As a goalkeeper, Tay is able to draw some parallels with his day job.
"Goalkeepers are very analytical, very much like doctors," he said.
"We learn about geometry because in water polo we rarely face curling shots. Most are in straight lines so we have to judge our angles and how to cover as much area as possible. We also assess our opponents and look at things from a macro perspective - their strengths, how they line up, how they take their shots.
"We look at the opponents' goalkeepers and try to see what their weaknesses are, if they are weak at handling bouncing shots for example, so we can tell our teammates what shots to go for.
"We pick these up as subtlely as doctors do to understand a patient's condition.
"But, most of all, it is passion that keeps me in both jobs."
This article was first published on May 02, 2015.
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