Fairytale win for Britain's poster-girl Jessica Ennis-Hill

Olympic champion Jessica Ennis-Hill completed a fairytale comeback by winning her second world heptathlon title on Sunday following an astonishing meltdown by fellow Briton Katarina Johnson-Thompson.

Ennis-Hill, returning to the sport after giving birth last year and battling a series of niggling injuries, was all but gift-wrapped the gold medal in Beijing after Johnson-Thompson failed to post a mark in the long jump.

World champion in 2009, Ennis-Hill capped a memorable two days by storming home to win the final 800 metres heat in two minutes, 10.13 seconds and finish as the runaway winner with a season-best total of 6,669 points at the Bird's Nest stadium.

"This is definitely one of the greatest moments in my career," said Ennis-Hill, draped in a Union Jack flag. "To be honest me and my coach didn't talk about the gold medal, I didn't think about it.

"I thought it would have been a little bit too far out of my reach," added the 29-year-old. "We spoke about coming here and medalling -- to get a bronze would have been a huge achievement. To come away with gold, I don't think we can quite believe it."

Canada's Commonwealth Games winner Brianne Theisen-Eaton, the gold medal favourite coming into the competition, settled for silver with 6,554 while Latvian Laura Ikauniece-Admidina claimed bronze with a national record 6,516.

"It was an emotional roller-coaster," said Theisen-Eaton. "In the javelin my groin got tight so I went home and iced. But I'm satisfied. Before the 800 I knew there was no way I could get the gold medal."

A disconsolate Johnson-Thompson finished 28th and last on 5,039 points, with eight competitors having previously dropped out.

The 22-year-old came unstuck after unwisely deciding to go for broke in the long jump, attacking the board aggressively in a bid to claw back some of Ennis-Hill's overnight advantage in the sweltering conditions.

But her high-risk strategy backfired as she fouled her first two attempts and was red-flagged again despite landing a huge third jump, leaving her devastated and prompting an official protest from British officials which was quickly withdrawn.

Ennis-Hill, who nailed a season's best jump of 6.43 metres, gave her young rival a comforting hug after watching her suddenly crash out of medal contention from second overall.

A javelin throw of 42.51 metres then put Ennis-Hill on the brink before she completed formalities with a rousing finish, overtaking Theisen-Eaton on the back straight.

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