Murray prefers hardcourts but is hoping to find his form on clay
Alex Corretja says Andy Murray can be a winner on clay after preparing the Scot for the start of his clay-court season in Monte Carlo on Monday.
The two-time French Open finalist says Murray just needs to appreciate the patience required on the surface.
Corretja told BBC Sport: "He's good anywhere and on clay he can also be very good.
"We're trying to make him understand that on clay you need to be patient and put a lot of balls on court."
The Spaniard, who climbed as high as two in the world rankings and twice reached the final at Roland Garros before retiring in 2004, says Murray has "huge potential".
The 20-year-old has a poor record on clay, winning only four of his 13 matches on the slower surface and failing to get beyond the first round of the French Open in his only appearance in 2006.
Sometimes you talk to people and they don't get it right away but for him even before you finish he knows what you're going to say
But Corretja, whose agreement with Murray runs until the end of the French Open, which starts on 26 May, has no doubt that record will improve.
"It's more like a mental issue to make him realise he can play well on this stuff - he has no reason why he cannot play on clay.
"You need to stay calm and not get too stressed, otherwise you get tired.
"He just needs to prove himself but we think we are on the right way."
Corretja, however, admits his stint with Murray in Barcelona has convinced him that one of the Scot's biggest strengths - the speed of his thought - is also a hindrance at times.
"He absorbs everything," he added. "Sometimes you talk to people and they don't get it right away but for him even before you finish he knows what you're going to say.
"In a way it's good because he learns fast but sometimes he needs to go slowly."
Murray opens his clay-court campaign against Feliciano Lopez in Monte Carlo.