Andy Murray not feeling blue despite his absence in Madrid

Of the world's top four players only Rafael Nadal has more clay-court matches under his belt this season than Andy Murray, but as the Madrid Masters unfolds this week the Scot will still have good reason to regret his enforced absence.

Although a lack of court time should not be an issue for Murray, who pulled out on Friday with a back injury, this is a stage of the season where the top players need to feel that their game is in good order to face the challenges ahead. The French Open is less than three weeks away and the leading men will expect to play in just two more events – Madrid and next week's Rome Masters – in the build-up to the year's second Grand Slam tournament.

Murray expects to be fit for Rome, which is regarded as the best test before Paris in that the conditions are similar to Roland Garros. In contrast, players have queried the value of Madrid – where the balls fly appreciably faster through the air due to the high altitude – and Murray's only consolation is that playing on blue clay this year further distances the event from the French Open.

That is the brainchild of former player and modern-day entrepreneur Ion Tiriac, who insists that the surface enables players and spectators to see the ball more easily. Most of the players have opposed the idea.

Nadal regards it as an unnecessary promotional gimmick – "the history of the clay-court season was on red – it wasn't on blue," he said – while Novak Djokovic said after his first practice session that the bounce felt low. Yet the tournament organisers and court builders insist that the blue dye is the only significant difference with a red clay court.

Whether the court was red, blue or in pink and purple stripes, Nadal would start as favourite. The world No 2 underlined his position as the king of clay with victories in Monte Carlo and Barcelona last month.

Djokovic beat Nadal in the finals in both Madrid and Rome last year, but the world No 1's clay-court season has yet to take off, his only previous tournament in Monte Carlo having been interrupted by the death of his grandfather. Roger Federer, meanwhile, will be making his first appearance on clay and the world No 3 faces a tough start, having been drawn to face either Milos Raonic or David Nalbandian.