Defending champion Gary Anderson booked his place in the quarter-finals of the William Hill World Darts Championship with a 4-2 win over Benito van de Pas at Alexandra Palace.

Anderson, the second seed, held off a spirited display from 23-year-old Dutchman van de Pas to open up a 3-0 lead without missing a double and producing nine maximums.

After the Scot had missed a dart at double top to win 4-0, Van de Pas rallied to reduce the deficit to 3-2.

However, Anderson - aiming to win the Sid Waddell Trophy for the third time in a row - made sure of a place in the last eight as he closed out victory with a match average of 107.8, which was the highest of the tournament so far.

Wednesday's late match then saw Raymond van Barneveld knock out last year's runner-up Adrian Lewis with a thrilling 4-3 win.

Fifth seed Lewis, who won the PDC world title in both 2011 and 2012, took the opening set before Dutchman van Barneveld, the 2007 champion, levelled with a 70 checkout.

Van Barneveld, a four-time winner of the BDO world crown and beaten by 'Jackpot' Lewis in last year's PDC semi-final, moved ahead at 2-1.

However, Lewis made the most of the Dutchman's failure to finish off the fourth set and squared the match once more.

Lewis maintained his momentum with a 106 checkout to take the fifth set for a 3-2 lead, only for Van Barneveld to find his range on the doubles again and force a decider.

It was the Dutchman who then held his nerve to deliver a 52 checkout with the final dart at double 16 which secured the set 3-1 and a place in the last eight against either Phil Taylor, the 14-time PDC champion, or Belgian Kim Huybrechts on Friday.

Earlier on Wednesday, Peter Wright, James Wade, Jelle Klaasen and Huybrechts all recorded comfortable second-round victories.

Number three seed Wright defeated Welshman Jamie Lewis 4-0, in which he dropped just one leg en route to the last 16, while Wade saw off veteran Steve Beaton, the 1996 BDO world champion, 4-1.

Dutchman Klaasen, who won the 2006 BDO world title as a 21-year-old outsider, beat Brendan Dolan of Northern Ireland 4-0 during which he twice came close to a nine-dart finish.

Huybrechts also produced a convincing display as the 13th seed defeated German Max Hopp in another straight-sets win.

Klaasen will next meet Dave Chisnall, with the winner then set to take on Anderson for a place in the semi-finals.