Shane Warne's mentor Terry Jenner believes the ace leg-spinner is trying to bowl too flat and fast and would need to change his tactics if he has to take wickets in the second cricket Test at Chennai starting on Thursday.

Jenner said Warne, who had a match haul of 4-193 in 60 overs against India in the Bangalore Test, needs to slow down in an attempt to regain the flight and drift which were his hallmarks.

"I thought he tried to bowl too quickly and that was not natural for him," Jenner was quoted as saying by The Courier Mail in Sydney on Tuesday.

"It looked to me as if the effort of bowling so quickly took so much out of him, he became exhausted and that allowed the tailenders to get after him.... I would like to see him slow down a bit and go back to the way he used to get 500 Test wickets.

Warne came to India needing just six more wickets to overtake Sri Lanka's Muttiah Muralitharan as the world's highest wicket-taker in Tests.

Jenner said every spinner has a speed limit above which the amount of turn he gets decreases.

"When Shane started out he was up at the 87km/h mark which I felt was a bit quick.

"Knowing Shane, I'm sure he would have been fitting into the team plan. I'm not there so I don't know that plan but I would hate to see the greatest leg-spinner of all time become a stock bowler.

"The problem when Shane tries to bowl too quickly is that his arm drops and he starts to bowl short, which is just not him.

"Also, he loses the most special quality he has ... drift (from off to leg through the air)," Jenner said.

"He can beat batsmen with drift and flight as he did in Sri Lanka. The trouble with bowling quickly is that it makes it hard to bowl variation balls like the wrong 'un which I did not see a lot of."