CLAIMS that Muirfield, home of the 142nd Open Championship, was "unplayable" were last night rebuffed by veteran golfers and the organisers.

As temperatures soared into the high twenties, Ian Poulter and Phil Mickelson added considerable heat to the debate over whether the course was playing too fast and that greens and pin placings were making the tournament a farce.

Poulter, who carded a one-over 72, said some of the pin positions were a "joke" and the 18th needed a "windmill and a clown face", like a crazy golf course.

Mickelson hoped organisers the R&A would "let go of their ego and set it up reasonable" after he shot a 69.

However, Peter Dawson, chief executive of the R&A, said the course was "playable but indeed very testing".

He added: "I do understand some players get frustrated. Ian Poulter bogeyed four of the last five holes – he was bound to get frustrated. It's a very testing, tough Open championship. It is far from unplayable."

But he said: "We do hear player comment and we are not so insular as to ignore it."

Mickelson, a four-time major winner, said: "I got very lucky to play early today because as the day wore on and we got to the back nine, about a third of every green started to die and became brown. The pins were very edgy too, on slopes and what. The guys that played early had a huge, huge break because even without any wind here, it's beyond difficult."

However, Mark O'Meara, the 1998 Open champion, denied conditions were unfair after returning a 67 in the afternoon. "I thought it was tough, it was challenging but not unfair," said the 56-year-old. "If they think that way they need to look at the old man and say: 'How did he do it that way?'" He added: " I'm not a big fan of guys who go out there and whine a lot."

Tiger Woods, who shot a 69, avoided direct criticism of the course but admitted: "I could see how guys were complaining about it." The 14-time major winner played in the most testing conditions in the afternoon as the sun and a drying wind made the greens impossibly slick.

The course took its toll of big names with Louis Oosthuizen, the 2010 Open champion, succumbing to injury and pulling out on the ninth hole and Rory McIlroy, the world No.2, shooting a 79 and admitting he was "brain dead " on the course.

As the 24-year-old Northern Irishman lamented his state of mind, Nick Faldo denied his comments earlier in the week about McIlroy's commitment were meant as a criticism, "I'm trying to give him a a little caring, loving help here," said the six-time major winner. Faldo said he was playing the role of a "grandad" to the young player, advising him to give full attention to matters on course rather than off it.