The 28-year-old Portuguese has been scouted by Walter Smith's backroom staff and it is thought he will cost the Govan club around £3million if they want to capture him when the January transfer window opens.

It is believed Italian giants Roma and Lazio, and Greek side Panathinaikos, are also tracking the player but he is keen to make the move to Rangers, who have also been linked with Spartak Moscow stopper Martin Stranzl.

"Sporting Lisbon are a big club and I am very happy here - but Rangers are massive," Tonel told the Evening Times.

"I know they have been out to see me on a couple of occasions and have been following me for over a year. That is very flattering for any player.

"I have played against Rangers at Ibrox with both Maritimo and then Sporting Lisbon last year in the UEFA Cup and it was an amazing experience. On the first occasion, I was with Maritimo back in 2004 and we lost on penalties and I will never forget the passion of the Rangers supporters.

"Then, last year with Sporting, I was back again and it was another great atmosphere. But I hope maybe I can play at Rangers wearing the home colours in blue and white."

Tonel has vowed that should he emulate Portuguese countryman Pedro Mendes in securing a move to Ibrox, he would not be using the Glasgow giants as a stepping stone to the Barclays Premier League.

"What I can say to the Rangers fans is that any contract I sign with Rangers I will honour to its end," he said.

"It is my hope that I may be able to play for Rangers in the Champions League next season and again after that.

"If it does happen, I will not be coming for one season and then be leaving the next."