Snooker World Championship: Ken Doherty's outstanding Crucible record has been shaped to a large extent by his ability to come through in tight finishes. The 1997 champion will need to show that quality again today, as he resumes at 8-8 in his quarter final here against Marco Fu.

Having finished Monday's second-round clash with Matthew Stevens with a run of five straight frames, Doherty continued his winning sequence by taking the first two against Fu, only to be pegged back to 2-2 at the mid-session break of the first session.

Doherty was in control of the fifth frame but ended up missing the last red to let Fu back in for a winning clearance, and despite leading 61-0 in the next, the Dubliner ended up losing that as well after Fu cleared from green to pink.

The world number 24 put together a clearance of 121 to win his fifth frame in a row but crucially, Doherty stopped the rot by taking the last of the morning to emerge from that opening session only 5-3 down.

Doherty struggled in the first frame of the night as Fu stretched his lead to 6-3, but the Irishman settled himself to turn a modest chance into a winning 76 in the next, and with further runs of 60 and 59 he went to the next interval in much better shape at 6-6.

When Doherty added frame 13 on the brown he led the match again, and just when he looked like losing the next frame, he doubled the last red and cleared up to lead 8-6.

Fu had then lost five frames in a row, but he responded by winning the last two of the day, finishing with a break of 110 to give himself every chance of being only the second Asian player ever to reach a world semi final.

In addition to the title, and the first prize of £200,000, Doherty also has a chance to become world number one when the annual list is finalised after the championship. The 36-year-old will definitely top the rankings if he lifts the trophy, and a win over Fu may even be enough if other results go his way.

If Doherty does get through today, his semi-final opponent is likely to be Peter Ebdon.

Ebdon compiled a clearance of 116 and three other breaks over 50 on his way to a 7-1 lead over Shaun Murphy, who is attempting to be the first player to retain the world title since Stephen Hendry 10 years ago.

After concluding his 13-2 win over David Gray with a run of nine straight frames, Ebdon extended it to 16 by taking the first seven against Murphy.

Ronnie O'Sullivan started his match against Mark Williams with a break of 90, but Williams levelled with a break of 94 and won the third on the black, during which O'Sullivan was given a warning by referee Jan Verhaas for foul language. The Welshman went on to lead 3-1 and later 4-2, before O'Sullivan took the last two frames of the day.