Kyrgios just wobbling a bit here and allows Nadal to take a 15-30 lead - the first time Kyrgios has been behind on his serve in this match. But, yep, you guessed it, another ace follows and we remain on serve at 2-2.
Huge, huge forehand from Nadal and Kyrgios just watches it fly by and we’re still on serve at 2-1 in the second. Meanwhile, we now know who the winner of this match will play in the quarters as 8th seed Milos Raonic comes back to beat 10th seed Kei Nishikori 4-6 6-1 7-6(4) 6-3.
First test passed. And second. Pushes Nadal wide and yet another ace and it's set point again.
Kyrgios fails to clear the net with the first and a 112mph second serve and 4-0 is suddenly 4-3. Test of Kyrgios' nerve now.
Big backhand puts Kyrgios into a 4-0 lead, but a sloppy backhand gives one of the breaks back to Nadal. 4-1 now and two serves from Nadal coming up.
Kyrgios holds serve then outlasts Nadal in the longest rally of the match so far at 16 strokes. Nadal then pushes a backhand into the net and it's 3-0 Kyrgios in the tie-break.
"NOOOOO!" Kyrgios pulls his return wide and screams into the south London sky. Nadal holds on and we're going into a tie-break to settle this first set.
OUT! Wait ... Is it? Kyrgios challenges and Hawkeye tells us it was the right call - but it was barely millimetres. Back to deuce...
But hang on! Some wonderful defensive work from Kyrgios takes it to deuce and an unbelievable return and it's set point...
And that's why he is World No.1. Ace, booming forehand, net volley, unstoppable backhand and it's game point Nadal...
Now it's Nadal who's worried... 0-30...
There's the first set for Novak. 6-3 in 24 minutes
Tsonga serving to stay in the set, here
Grigor Dimitrov two sets to the good against Leonardo Mayer. The winner faces Andy Murray in the quarter-finals
Djokovic with the break. Leads 4-2 against Tsonga in the first set
Murray holds for 6-5. Anderson serving to stay in the match
Anderson holding firm here. Saves five breka points to hold. Murray's break-point conversion rate is just 21% at the moment - 4 from 19
And a fourth, as Murray does brilliantly to return before Anderson fires wide
Third break point for Murray
Cilic makes heavy-going of the third set but he's finally through 7-6(8) 6-4 6-4. He'll face Novak Djokovic or Jo-Wilfried Tsonga in the quarters
Murray's likely quarter-final opponent Dimitrov takes the first set against Mayer. 6-4 and the Bulgarian is going about his business is ruthless fashion
Out on Court No.18 Marin Cilic is serving for the match against Jeremy Chardy
Hold on... Murray's broken Anderson already. He needed three attempts to do it mind, but the South African's serve is tipped as his biggest (perhaps only) weapon. It's 2-1 in the first set, Murray to serve
No chance of a fourth tie-breaker in four sets in the Lopez/Isner match. Lopez breaks the American to take the fourth 7-5 and the match. He'll face Stan Wawrinka in the round of 16
The big-serving Anderson holds his opening game. Elsewhere, Dimitrov is 3-3 with Mayer in the first set
Eyes now turn to Centre as Andy Murray gets started against the giant Kevin Anderson. There aren't many men who make the 6ft 2in Murray look small, but Anderson towers over the British No.1
And the 2011 champ takes it, needing just an hour to dispatch Peng 6-3 6-2
Match point for Petra Kvitova against Shuai Peng out on Court No.2...
While Andy Murray prepares to take to Centre Court for his fourth-round clash with Kevin Anderson, his potential quarter-final opponent Grigor Dimitrov is underway on Court No.1. He's 1-0 up in the first set against Leonardo Mayer
After three tie-breakers in three sets, Lopez and Isner are still on-serve at 3-3 in the fourth
There it is. Eugenie Bouchard reaches the Wimbledon quarter-finals for the first time, beating Serena's conqueror Alize Cornet 7-6(5) 7-5 in one hour 46 minutes
And it's Lopez that takes it (7-3) to lead by two sets to one
Surprise, surprise - Isner and Lopez have gone to a tie-breaker in the third!
2013 runner-up Sabine Lisicki books her place in the fourth round with a 6-4 3-6 6-1 victory over Ana Ivanovic on No.1 Court, sealing the win after one hour and 50 minutes with a love service game
April 10: Free practice 1