They may be winless this season, but Bulls captain Pierre Spies still rates the Crusaders a bigger threat than the Blues.

The Auckland-based Blues had a blistering start to the season - scoring 68 points and nine tries, including a 34-15 demolition of the Crusaders.

However, last week the Bulls lowered the Blues' colours with a dominant performance at Eden Park - winning 28-21 and preventing the Blues from getting a four-try bonus point for the first time this season.

In stark contrast the Crusaders have looked a far cry from the team that won seven titles between 1998 and 2008.

Spies believes the Crusaders showed enough in their one-point (28-29) loss to the Hurricanes last week to ensure they remain a major threat.

"They are such a quality team and a franchise with pride," Spies said in a teleconference call from the Bulls' base in Christchurch - where the men from Pretoria will tackle the Crusaders on Saturday.

"This a big game for them," the Bulls skipper said, adding: "They won't be happy with the two defeats, especially the last one which was within their grasp."

Spies said for the Bulls it is all about getting the right "mental preparation" for what they want to achieve on the field and ensure they execute that gameplan on Saturday.

"It is going to be a tough encounter, even tougher than the one at Eden Park [last week]," the burly Bok No.8 said.

Spies said the rich history of the Crusaders in Christchurch make it even more difficult to topple them at home.

In nearly two decades and over 100 Super Rugby matches the Crusaders have lost just 14 times in Christchurch.

The Bulls' predecessors, Northern Transvaal, boast just one win in this historic city - a 34-18 victory back in 1996.

Some of the Bulls' biggest defeats have also been in Christchurch - such as their 27-75 humiliation in 2000.

"The Crusaders is a very successful franchise," Spies said, adding: "There is a lot of rugby culture in the Crusaders set-up and they have a very high success rate when playing at home."

The Bulls skipper did not feel that the Pretoria team's win over the Blues last week will make the Crusaders more fearful of the visitors this week.

"The people may have taken note of our win," he said, adding: "However, this is a new week and a new challenge.

"What happened last week will have to influence on this week.

"The Crusaders are at a stage where they need to bounce back and rectify their poor start [to the season] and we are ready for that challenge.

"The [Bulls'] victory at Eden Park won't means much if we don't follow it up with another successful game this week."

By Jan de Koning