Adams is into the last four for a third straight year

The top seed made a timely breakthrough against the throw in the eighth set and finally hit a winning double five after missing seven darts for the match.

He will play number five seed Mervyn King in the semi-finals.

King came from 3-0 down in a nailbiting clash with number four seed Tony Eccles before prevailing 5-4.

Adams led 2-0 early on before 2000 champion Hankey, after a typically slow start, found his form to level at 2-2.

But "The Count" was left to rue a narrow failure on a 138 checkout in the decisive leg of the seventh set.

That would have given him a 4-3 lead, but instead that advantage went to Adams, who then broke his opponent's throw and capitalised as Hankey missed a host of chances.

"It feels absolutely marvellous to be in the semi-finals again," said England captain Adams, through to the last four for the third consecutive year, having lost the 2005 final to new PDC champion Raymond van Barneveld.

Give me another 12 months and I'll be back to where I should be - a really serious contender Ted Hankey

"It was a very similar match to two years ago from 3-3, although this time Ted wasn't getting as frustrated when he missed doubles - or if he was, he wasn't showing it outwardly.

"I got another opportunity when Ted just missed the 138 and that may have hurt him a bit more than I thought at the time."

As for his problems closing the match out, the 50-year-old from Peterborough said: "I was just thinking 'for God's sake, hit it'. They say the last double is the hardest and you tighten up."

Despite his loss, Hankey was far from unhappy, having put behind him a terrible 2006 with his performances in this tournament.

"I enjoyed it," said the 38-year-old Telford-based player. "I was laughing and smiling for quite a lot of the match because no matter what I did, Martin was always better.

"I played really well, it was a good game and I'm really happy to have reached the quarter-finals. We've had a rough ride but give me another 12 months and I'll be back to where I should be - a really serious contender."