The fist pump, the roar. Murray screams so loud that the Christ the Redeemer statue asks him to keep it down. The defending champ is back level is the decider.

Murray slices and dices, eventually showing the sort of power that Johnson can't hand with. Break point...

While Murray battles on, Amber Hill is preparing for the semi-finals of the women's skeet. From 19:00, the Briton will be part of the six-woman semi-finals. Top two into the final, next two shoot for bronze, bottom two go out. 30-minute warning.

Now then. Andy Murray's Olympic title defence is in serious peril. After coming so close to breaking the Steve Johnson serve in the previous game, he gives away his own, Johnson moving ahead with a lob that has Murray blasting away a ball in frustration.

By hook or by crook, the American holds his serve, the game sealed with the dinkiest of drops over the net. Deeper into this decider we go.

Johnson's serve is looking about as reliable as the waistband of a 50p pair of pants here. The forehand isn't much better. It's a right old ding-dong, the American just clinging on. It feels like a defining moment...

The sun is out, a surprisingly rare sight for an Olympic Games in Rio. For most of the time the weather has been more Bradford than Brazil. Andy Murray, the 2012 champ, is pressuring Steve Johnson, looking for a break. A heat-seeking backhand refuses to kiss the line, much to Murray's annoyance. This game, though, is going on...

A score of 47.550 gives Page the lead after what is the first of her two qualifying routines. There are 16 women in the field, with the top eight qualifying for the final.

While Andy Murray searches for that break in the final set, Crewe's Bryony Page has just taken to the trampoline. Bouncing high enough to touch the ceiling...

Image source, Getty Images

Britain's 2013 US Open champion Justin Rose and Sweden's Open champion Henrik Stenson are in contention for medals after their second rounds on the Olympic Golf Course.

Rose, 36, is tied for fourth with France's Gregory Bourdy, with both men four shots off Australian leader Marcus Fraser, who is 10 under par with three holes still to play on his round.

World number five Stenson is in the club house in second place, two shots off the lead at Reserva de Marapendi.

A little earlier on I was getting my American Johnsons mixed up. Andy Murray is playing Steve the tennis player not Shawn the gymnast. Imagine how grumpy he'd be seeing his opponent doing tumbles and tkatchevs at the other end. Anyway, we're on serve in the final set...

Could this be the eighth discipline in the new Olympic Octathlon?

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Tom Fordyce
Chief sports writer in Rio

Sensational first morning of the heptathlon. If you're wondering how respective PBs stack up across the remaining two events on day one, it looks like this:

Shot put: KJT 13.14m, Thiam 15.24, JEH 14.79

200m: KJT 22.79 secs, Thiam 24.78, JEH 22.83

It's heat time in the pool, building towards another evening of finals in the small hours. Great Britain's Fran Halsall has won her 50m freestyle heat to reach the semi-finals, beating world number one Cate Campbell. 

It's all a bit quiet on the water at Marina da Gloria.

All races are currently postponed due to poor conditions.

Perfect excuse for a nap, apparently...

That will do. Just like yesterday, Andy Murray must win a deciding set to continue the defence of his Olympic title. The winner will meet Gael Monfils or Kei Nishikori in the last four.

Image source, EPA