Novak Djokovic overcomes China's Wu Yibing 6-4 5-7 6-4 6-4 in gruelling Centre Court battle to reach Wimbledon second round
British men's number one Cameron Norrie loses in five sets to qualifier Michael Zheng - one of 10 home players to lose on opening day
Jack Draper pulled out of championships because of arm injury to join Emma Raducanu on sidelines
Men's champion Jannik Sinner overcomes Miomir Kecmanovic in five-set thriller
Women's top seed Aryna Sabalenka beats Teodora Kostovic 6-2 6-3
Sinner 4-6 6-3 6-7 (6-8) 3-2 Kecmanovic*
Jannik Sinner picks up his 23rd ace of the match to lead 30-0 and kicks on further to wrap up the hold to love.
All five service games in this second set have been very routine - it's not quite telling the full story of what we've seen across the opening two sets.
We're just sitting and waiting for the latest twist.
*Sinner 4-6 6-3 6-7 (6-8) 2-2 Kecmanovic
Jannik Sinner's record in five-set matches, which he'll need this to be if he's to book a spot in round two, is not great.
The Italian has won just one of his last nine.
Miomir Kecmanovic gets through his latest service game without any major drama.
*Zheng 6-7 (7-9) 6-2 6-7 (2-7) 6-3 3-4 Norrie
Cameron Norrie holds to 15. More fist-pumping.
He's had a foothold in all three of Michael Zheng's fifth-set service games - 30-all in the first two, deuce in the previous one - but no break points.
Image source, Getty ImagesSinner 4-6 6-3 6-7 (6-8) 2-1 Kecmanovic*
Tim Henman
Former British number one on BBC One
It would seem the blood on Jannik Sinner's shoe isn't causing him any trouble at the moment because he hasn't called for the trainer.
We first saw that blood a long time ago, so it will be interesting to see what he says about that injury after the match.
But his focus of attention right now is trying to get a break of serve in this fourth set.
Sinner 4-6 6-3 6-7 (6-8) 2-1 Kecmanovic*
Despite that blood seeping out of Jannik Sinner's shoe, he seals a fairly comfortable hold to love.
Can Sinner now apply some pressure to Miomir Kecmanovic's serve?
Zheng 6-7 (7-9) 6-2 6-7 (2-7) 6-3 3-3 Norrie*
Michael Zheng's serve delivers for him once again - an ace down the T at advantage to secure the hold. Nerveless serving.
*Sinner 4-6 6-3 6-7 (6-8) 1-1 Kecmanovic
Jannik Sinner gets a chance at 30-30 but yet another surprising rash shot from the Italian spurns the opportunity.
The world number one then floats a backhand into the net as Kecmanovic holds, bringing surprised murmurs from the Centre Court crowd.
Television pictures are showing what appears to be blood stains on the top of Sinner's shoe. I wonder if that's restricting his game?
Image source, Getty Images*Zheng 6-7 (7-9) 6-2 6-7 (2-7) 6-3 2-3 Norrie
Excellent return of serve from Cameron Norrie to bring up deuce. All Michael Zheng could do was block it into the net.
Is this the moment for Norrie?
*Zheng 6-7 (7-9) 6-2 6-7 (2-7) 6-3 2-3 Norrie
Naomi Broady
Former British player on BBC Radio 5 Live
We've flip-flopped so much set-by-set with momentum that we feel if we stay to pattern, Norrie is going to run away with it but you just never know in a deciding tie-break.
They feel pretty evenly-matched.
Image source, PA Media*Sinner 4-6 6-3 6-7 (6-8) 1-0 Kecmanovic*
Jannik Sinner could really do with a confident start to this fourth set and he gets it with a hold to 15.
Not since 2003 has the defending men's champion lost in the first round at Wimbledon, when Lleyton Hewitt lost to Ivo Karlovic.
Sinner will be hoping that stat can remain intact for another year.
*Zheng 6-7 (7-9) 6-2 6-7 (2-7) 6-3 2-3 Norrie
Cameron Norrie buries a forehand down the line with Michael Zheng running across the baseline in the opposite direction to cover the gaping court. 30-0.
Zheng levels the game - an inside-out forehand on the approach for the first point, a forehand error from Norrie for the second - but Norrie keeps his composure to hold.
The deciding set is going with serve.
Sinner 4-6 6-3 6-7 (6-8) 0-0 Kecmanovic*
Harry Poole
BBC Sport at Wimbledon
Goodness me. There were deafening cheers inside Centre Court after Miomir Kecmanovic came out on top in that quite stunning rally to level the tie-break at six points apiece.
The crowd could not contain themselves throughout as both players dug out remarkable shots all around the court, and they rightfully rose to their feet in appreciation.
It's Kecmanovic getting all the appreciation now, though! The 50th-ranked Serb is a set away from a first-round giant-killing, and you have to say, Jannik Sinner looks very vulnerable here.
Zheng 6-7 (7-9) 6-2 6-7 (2-7) 6-3 2-2 Norrie*
Cameron Norrie lets out a quiet "come on" after forcing a forehand error for 15-all. He's really trying to amp himself up.
The pair trade points for 30-all.
Zheng responds with an ace down the T - he's had a lot of success with that particular serve - before closing out the hold with a cool cross-court volley.
Image source, Getty Images*Sinner 4-6 6-3 6-7 (6-8) 0-0 Kecmanovic
Andrew Castle
BBC Sport tennis commentator on BBC One
This is absolutely inspired. We could have a major shock on our hands here! The defending champion is in real trouble now because his five-set record is horrendous.
Miomir Kecmanovic is doing so well to stay in these rallies under the barrage from Jannik Sinner.
*Sinner 4-6 6-3 6-7 (6-8) 0-0 Kecmanovic
The upset is on!
They finally get into a rally and it's Miomir Kecmanovic who stays the course when Jannik Sinner sends long.
Centre Court came out to see Sinner today but it's Kecmanovic who is creating the headlines so far.
Image source, Getty Images*Sinner 4-6 6-3 6-6 (6-7) Kecmanovic
Nervy times for Jannik Sinner.
He begins with a let, then a fault, then another let...
Gasps from the crowd.
*Sinner 4-6 6-3 6-6 (6-7) Kecmanovic
Andrew Castle
BBC Sport tennis commentator on BBC One
Oh my goodness! What a rally. The crowd rose even before that magnificent point was over.
We are being treated to a decent first match on Centre Court this year.
Image source, PA Media*Zheng 6-7 (7-9) 6-2 6-7 (2-7) 6-3 1-2 Norrie
Norrie nails a cross-court smash winner. Michael Zheng sends a forehand long.
Norrie roars. Deuce safely navigated. An important hold.
*Sinner 4-6 6-3 6-6 (6-7) Kecmanovic
Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Live
The crowd are on their feet. Extraordinary effort from both fellas there.
Kecmanovic battling for survival and fair is fair.
*Sinner 4-6 6-3 6-6 (6-7) Kecmanovic
Wow. Centre Court is on its feet.
Both Jannik Sinner and Miomir Kecmanovic need to take a bow after that one.
Sinner is flying from one side of the baseline to the other desperately trying to return and he manages - somehow - to get three back as he barely keeps his feet. Eventually it ends with a volley winner from Kecmanovic at the net. Point of the match.
A winner down the line gets Kecmanovic back in front and set point.
