Mark Warburton questioned the decision to replace the maligned Hampden Park pitch just days before Rangers' Scottish Cup semi-final clash against Celtic.

The pitch at the national stadium, which has been criticised for its quality, was replaced less than three months ago ahead of the League Cup final but will be relaid with work starting on Monday.

Speaking after Rangers' Petrofac Training Cup final win over Peterhead, Warburton admitted that the standard of the surface was not good enough, but has questions over the call to replace it so soon before the Scottish Cup semis.

"The pitch was difficult," he said. "You saw the first 10-15 minutes we couldn't get the ball down to play. It was hard to play on.

"I know a lot of work is going on, I appreciate that, but you've got to question how a new pitch can go down [so quickly].

"My concern is if we have any adverse weather. If we have adverse weather Thursday or Friday and you have Hibs playing Dundee United on the Saturday and you have Celtic versus Rangers on the Sunday.

"I'm not sure how you bed in a new pitch in three days. But I'm no expert on surfaces.

"I understand there is problems. Problems can occur and you have to find a solution and deal with them.

"But there are big games coming up on the pitch here, it's a national stadium and it is surprising.

"How much does that cost? I'm no expert but the amount of times it's being done... do you put down one of the more expensive options at the beginning which becomes the cheaper option in the long run?

"We want the best playing surface possible. Our concern is that there's a highly competitive game being played on it 24 hours before."