TIMANA TAHU was devastated he had to return to Sydney this week after suffering yet another hamstring injury but his departure from the Wallabies has left Robbie Deans with an added disappointment - the coach cannot continue with his big experiment.

Deans has major plans for Tahu for next year, which include using him in an intriguing attacking and defensive role. He had hoped to give Tahu ample game time on the tour, where he could play him at inside centre in attack and outside centre in defence.

But with the centre tearing his hamstring against Italy in Padova, this will have to wait until next season.

Nonetheless, Deans is certain to be in contact with Waratahs coach Chris Hickey to determine whether Tahu can be used in a similar way during next year's Super 14.

After Tahu's problems at No.12 against the Springboks in Johannesburg in August, Deans asked the player if he was more interested in a roving defensive role.

Moving the former Kangaroo to outside centre when the opposition has the ball is fraught with danger, because No.13 is regarded as the most difficult defensive position on a rugby field because of the varying attacking alignments and the uncertainty over whether the fullback and blindside winger will come into the line.

However, Tahu was prepared to embrace the idea and it worked against Italy.

"When learning how to play inside centre, I found it was better for me to sit out and have a look how it all works," Tahu told The Sun-Herald.

"I have been studying both centre positions, analysing exactly what is going on in both defence and attack.

"Robbie asked me if I wanted to have a crack at defending at No.13. I thought at inside centre my brain was getting a bit scattered defending there, so I thought it would be a good idea to be on the outside looking in.

"I did feel comfortable at No.13 against Italy. Both of the positions are definitely hard. At inside centre you have people running at you, and there's a lot of traffic, whereas at No.13 you have to be a lot smarter."