Ennis in pole position for epic triumph after flying start and superb finish

Briton enjoys healthy heptathlon lead thanks to record hurdles and blistering 200m

A flying start and a flying finish. Jessica Ennis opened day one of the Olympic heptathlon with the bang of a stunning British record in the 100m hurdles, 12.54sec. She concluded it with the bang of a lifetime best in the 200m, 22.83sec.

It was perhaps just as well, because in between had come if not quite a whimper in the high jump and the shot but slightly below par performances. All of which evened out into a strong pole position overnight for the would-be British golden girl.

With the long jump, javelin and 800m to come today, Ennis stands top of the pile with 4,158 points. That is an improvement of 45 points on her first day score at the Hypo-Meeting in Götzis in Austria in May, when the Sheffield woman broke Denise Lewis' 12-year-old British heptathlon record.

More to the point, Ennis has put clear daylight between herself and the women who were expected to be her most serious challengers. She leads by 184 points from Austra Skujyte, the 2004 Olympic silver medallist from Lithuania. Down in fifth, 258 points back, is Hyleas Fountain, the 2008 silver medal winner from the United States. In ninth and 10th are the other two medallists from Beijing, the Russian Tatyana Chernova and the Ukrainian Nataliya Dobrynska, respectively 309 and 323 points off the pace.

In other words, the gold medal is there for the taking. "Coming into this, I knew I was in good shape, but to be honest I couldn't have imagined performing like this," an elated Ennis said. "I've definitely exceeded my expectations today. I just want to have three really solid performances tomorrow and doing what I know I'm capable of. Today has been great, but there's still a lot more to work on for tomorrow. It's been a long day. I need sleep."

It was shortly after 10am when Ennis clocked on for her first shift of the day. When the 26-year-old was introduced at the start of heat five of the 100m hurdles, the 80,000 crowd threatened to raise the roof. The noise sent a shudder through the spine. To Ennis, quite clearly, it sent a surge of super-charged adrenaline coursing through the veins.

It took her six hurdles to get into the lead but by the finish she was clear of the opposition. She was also in a state of shock as the scoreboard flashed up her winning time: 12.54sec.

Ennis clasped her hands to her mouth, and with good reason. She had taken precisely a quarter of a second off her lifetime best. She had also smashed Tiffany Porter's British record, which stood at 12.68sec.

Her time would have been good enough to win individual 100m hurdles gold at every Olympic Games bar Seoul in 1988 and Athens in 2004. "That's crazy, so crazy," Ennis said, her face beaming. "I'm so shocked. I can't believe it to be honest. I really can't."

It was a truly breathtaking performance – the fastest ever 100m hurdles time recorded in a heptathlon, eclipsing the 12.62sec set by Eunice Barber of France in 2005. Jackie Joyner-Kersee, by a distance the finest all-round female athlete of all-time, clocked 12.69sec en route to her heptathlon world record score at the Seoul Olympics in 1988.

It just so happened that Joyner-Kersee was following events in the stadium yesterday. "That was just incredible," the American said.

It was that. It put Ennis joint third in the world rankings this year in the 100m hurdles, the individual event of which she is also entered for at London 2012. "I knew I was in good shape and hurdles has been going well," she said, "but if I'd run 12.80sec or 12.70 sec I would have been over the moon. To run 12.54sec, I just can't believe it."

The reception from the crowd also beggared belief. "It was weird," Ennis reflected. "I'm normally quite nervous before the hurdles but I kind of felt strangely calm. Then, just coming out into the stadium, and hearing the crowd, it was such an amazing feeling. It gave me goosebumps.

"Training has been going well, but when you're in this environment, with the crowd and the energy, it just all comes together and pushes you on."

It all added up to a mighty statement of intent, giving Ennis a huge advantage over her principal rivals, both materially – in terms of points – and psychologically.

The high jump ought to have been another major gain for the pride of the City of Sheffield Athletics Club – she is joint holder of the British record, 1.95m – but she has struggled to hit the heights, let alone find consistency, for some time now. It was the same yesterday.

Ennis could venture no higher than 1.86m.

There were consolations, though. Ennis had only jumped 1.85m en route to her British record score at Götzis in May. And Dobrynska and Chernova both failed to gain any ground.

Still, the mild disappointment was compounded in the shot. Ennis has thrown a lifetime best of 14.79m this summer but her best last night was 14.28m. Skujyte, a former shot specialist, produced a 17.31m throw to shoot into the lead, 64 points ahead of Ennis.

It was a different story, though, when it came to the final event of the day, the 200m, just around 9pm. Ennis shot out of her blocks and tore round the bend, battling for victory with the fastest sprinter in the field, the flying young Dutchwoman Dafne Schippers.

The latter was given the nod in a photo finish but both crossed the line in 22.83sec, a personal best for Ennis by 0.05sec.

"To end the day with a PB was brilliant," she reflected. "I think it's a combination of a hard, fast track, obviously it being the Olympics, and having this crowd behind everyone makes all the difference. "

She was not the only Briton smiling. Katarina Johnson-Thompson finished with a 23.73sec clocking, her third personal best of the day.

The 19-year-old Liverpudlian, who lies 14th, has been hailed as "the next Jessica Ennis." By 10pm today she ought to have a golden Olympic act to follow.

Missed vocation?

Jessica Ennis's time of 12.54sec in the 100m hurdles would have won her the individual gold at all but two of the past Olympics.