The 21-year-old from Uttoxeter ended the Britain’s 28-year wait for a men’s Olympic swimming gold overnight with the country’s first medal of the Games. Peaty broke his own world record, winning in 57.13 seconds and also broke the British medals duck after near misses for fellow swimmer Hannah Miley and fencer Richard Kruse.
Moments later Jazz Carlin scooped Team GB’s second medal when she won silver in the women’s 400m freestyle behind American sensation Katie Ledecky, who won in another world record.
There was drama in the tennis as the Murray brothers, Andy and Jamie, lost a thrilling contest 7-6 (8/6), 7-6 (16/14) to the Brazilian duo of Andre Sa and Thomaz Bellucci. Wimbledon champion and Team GB flagbearer Andy Murray had earlier comfortably won his singles first-round match against Victor Troicki of Seribia in straight but met with an inspired display by the hosts’ pairing.
However, as that disappointment was taking place on Court No 1, Murray’s hopes of defending his Olympic singles title received a boost next door on Centre Court as World No 1 Novak Djokovic lost in straight sets to Argentina’s Juan Martin Del Potro.
Djokovic, who also lost to Del Potro in the bronze medal play-off in London in 2012, had no answer to the power of the 2009 US Open champion, who sealed a 7-6 (7/4) 7-6 (7/2) victory in almost two and a half hours. The Serbian, who also suffered a shock early exit at Wimbledon last month, left the arena in floods of tears.
The loss by the Murray brothers means the top two seeds in both doubles competitions have already been eliminated, with top seeds Nicolas Mahut and Pierre Hugues-Herbert of France having lost to Colombia’s Juan Sebastian Cabal and Robert Farah.
Three-time champions Serena and Venus Williams suffered their first ever Olympic doubles loss to Czech pair Barbora Strycova and Lucie Safarova, while second seeds Kristina Mladenovic and Caroline Garcia of France were beaten by Japan’s Eri Hozumi and Misaki Doi.
The Murray brothers lost a tight first-set tiebreak against their Brazialian opponents but appeared to have recovered when they took an early break in the second set. However, in front of a sparse but vocal home crow, Sa in particular lifted his game and forced another shoot-out.
It developed into an epic battle as the British pair recovered from 6-3 down and went on to save three more match points.
Andy produced a stunning backhand volley from an acute angle to save the sixth match point but could do nothing when the seventh flew off the net cord.
Back at the pool, a dominant performance saw Peaty deliver Great Britain’s first medal before he proclaimed: “I did it for my country.”
Peaty emulated Adrian Moorhouse, the 1988 champion in Seoul who was in the BBC commentary box for the occasion.
Peaty added: “It’s so surreal to get Team GB’s first gold, but this product is seven years of work.
“I came out tonight and took the first 50 easy and came back with everything I have got. I did it for my country and that means so much for me.”
The Englishman was the only man in history to swim beneath 58secs entering the Olympics - and he remains so, having now done it four times.
He broke his own world record in Saturday’s heat, qualifying in 57.55 and was just 0.07 seconds slower in Saturday night’s semi-final.
And in Sunday’s final, Peaty went even quicker.
He completed the first 50m in 26.61, 0.08 under world record pace and a blistering second length saw him enhance his advantage.
Cameron van der Burgh of South Africa, the London 2012 gold medallist, was second in 58.69 and Cody Miller of the United States third in 58.87.
Peaty’s triumph was swiftly followed by Carlin’s fine silver.
The Welsh Commonwealth champion was always going to be aiming for second at best as the peerless Ledecky won gold in a world record of three minutes 56.46 seconds.
Carlin was the second-fastest qualifier and lived up to her billing, clocking 4mins 01.23secs to take silver as Ledecky’s compatriot Leah Smith took bronze in 4:01.92.
Carlin was making her Olympic debut after illness denied her a chance to compete at London 2012 and said she was inspired by Peaty.
She said: “I honestly can’t believe it. I am on the edge of tears, it hasn’t really sunk in at all.”
Elsewhere, Aberdeen’s David Florence beat Poland’s Grzegorz Hedwig by two-and-a-half seconds to finish first in the Canoe Slalom heats.
“It’s nice to get off to a good start,” said the Scot. “I feel things have gone pretty much to plan. Every run aim is to go out and what I plan to achieve from the start. That wasn’t too far off – there were no major errors – so it was good.”
Florence will now focus on the C2 heats with partner Richard Hounslow today.
Day Two of the Olympics was marred by high winds which led to the cancellation of the day’s rowing programme and a sickening crash in the women’s cycling road race.
The Netherlands’ Annemiek van Vleuten was hospitalised with concussion and three fractures to her lower back following her horrendous downhill crash 10km from the end of the 137km race, which she was leading at the time. Team-mate Anna van der Breggen went on to win the gold medal, with Britain’s Lizzie Armitstead fifth.
Van Vleuten was well enough to provide an update on her condition on Twitter, insisting that she was “fine”.
Indeed, despite the broken bones, she said her most painful thing was the way she exited the race.
She tweeted: “I am now in the hospital with some injuries and fractures, but will be fine. Most of all super disappointed after best race of my career.”
Great Britain’s women will face New Zealand in the semi-finals of the rugby sevens at 7pm tonight after beating Fiji 26-7 in the last eight.