Sharks coach John Plumtree has warned his players that the Bulls will bring threats all over the field when they play each other in a Super Rugby decider in Durban on Friday.

Defeat for the Sharks, currently in eighth place overall on 49 log points, will dump the coastal outfit out of the competition and put the visitors on the brink of playoff qualification.

It is a simple equation for the Sharks boss and he was fully aware of what lay at stake in their latest South African derby.

"It's another crucial game for both sides," Plumtree said.

"Both need the win and for some reason the last two or three seasons it's come down to a Bulls-Sharks clash.

"We did it to them last season and the year before they put us out.

"So it's finals rugby and a crucial game for both sides. There's no motivation needed."

Earlier this season, the Bulls won a tight contest 18-13 at Loftus Versfeld and Plumtree recalled how they fell apart.

"When we played them earlier in the season, we didn't look after all their threats," he said.

"We didn't get on top of them and hence they got the win.

"They put us under pressure, our discipline wasn't good enough and we didn't turn up on the day, so we have to turn that around."

The Sharks coach said he had witnessed some captivating play from the Bulls in recent weeks.

"I've been very impressed by the Bulls on the last three or four occasions," Plumtree said.

"They dominated the Chiefs forwards, they did the same to the Cheetahs and the Stormers, so they've been excellent.

"Their driving line-out, they're very clinical, winning ball is not really a problem for them, so they strangle the life out of you.

"They win the territory battle and their possession stats are right up there as well.

"We're going to have to turn that around somehow and that's what we've been working on the last couple of days."

Bulls coach Frans Ludeke also expected a tough, physical contest.

"It is going to be a huge clash like always playing against theSharks," Ludeke said.

"It is a physical battle and it is about basics. The small things will make a difference on Friday night.

"The Sharks improved -- all the sides improved -- but they had that unfortunate loss against a motivated Lions side.

"If you look at that game closely, it was a huge contest, so we don't expect anything different from them on Friday night."