Ken Doherty produced a brilliant comeback to move ahead in his second-round clash with Mark King at the Embassy World Championship in Sheffield last night.

The 32-year-old looked out of sorts during the morning session and deservedly trailed King 6-2. But after a tense opening last night, Doherty slowly moved through the gears to lead 9-7, and needs four more frames to clinch a quarter-final place.

The first frame of the evening session could have gone either way but it was Doherty who held his nerve to pot pink and black.

The Dubliner, who had struggled with his game earlier, looked relieved after closing the lead to just three frames.

However, King played a perfect plant into the corner to establish a slender lead in the 10th frame.

Doherty again showed his tactical awareness to keep in the frame, but King was fearless with some of his shots and restored his four-frame advantage.

King (28), is a confident break-builder and he took control of the next with a well-constructed 56.

But Doherty is a former world champion and dogged competitor, who capitalised on a mistake to snatch the frame with a 48 break.

The world number four also pulled back another frame with a 58 break before the mid-session interval.

Both players squandered opportunities in a scrappy 13th frame before Doherty took control to reduce the deficit to one.

Doherty was on a roll now and confident breaks of 71 and 60 moved him ahead.

He then opened a two-frame lead with a superb 94 clearance.

Earlier, Matthew Stevens scored heavily and ruthlessly to complete a 13-3 drubbing of Jimmy White with a session to spare and become the first quarter-finalist.

Not surprisingly, Ronnie O'Sullivan outclassed Robert Milkins, the world number 54 from Gloucester, by 13-2 to carry his title defence into a quarter-final against either Stephen Lee or Quinten Hann.