Rangers manager Walter Smith launched an astonishing attack on Celtic chief executive Peter Lawwell just 24 hours before the two sides meet in a crunch Clydesdale Bank Premier League encounter at Parkhead.

Lawwell criticised the Scottish Premier League's decision to extend the season if Rangers reach the final of the UEFA Cup, claiming it compromised the "sporting integrity" of the SPL.

Whether or not the Ibrox side reach the Manchester final, Smith's side - who played out a goalless draw in the first leg of their UEFA Cup semi-final against Fiorentina at Ibrox on Thursday night - will have to play four games in eight days in the title run-in.

Smith questioned Lawwell's motives in criticising the SPL, saying: "We have a 'sporting integrity' situation which gave me a good laugh.

"Peter Lawwell appears to be the person who is the chairman of the sporting integrity committee for the SPL.

"Peter would be better coming out and saying he wants Rangers to play four games in a week because it suits his team and helps their quest to retain the championship.

"If it was the other way about I would be hoping that Celtic had to play four games in a week. So he should be honest about it instead of trying to hide behind what he is calling sporting integrity.

"He's doing what he feels is the right for his club by saying the season shouldn't be extended, but he's doing it for his own reasons."

Smith believes Celtic have enjoyed plenty of preferential treatment at the hands of the SPL this term.

"The thing that bothers me most is that the SPL have this season acceded to every request Celtic have made," Smith continued.

"It's no coincidence that we are playing one of our biggest games of the season when they (the SPL) would have a fair idea that we would be playing it between two very important semi-final games.

"I don't mind playing four games in a week. Celtic are using that situation to their advantage, but that's what it's all about. We have got to overcome that if we are to win the championship.

"The most galling aspect is that they have given Celtic everything they asked for and Peter is still complaining."

Smith insists all the dissenters over the proposed extension of the season should instead focus on the good Rangers' European run is doing for the Scottish game.

"I don't take part in conspiracies. I thought it was a reasonably simple request to extend the season, but maybe I was being naive," Smith added.

"If Rangers are helping raise the profile of Scottish football, helping raise the co-efficient and giving us extra European places, then surely we should be getting a little bit of help.

"If the SPL think that's the way to treat their teams then that's fine.

"But over the piece, I think my own club has been treated unfairly."

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