Sep.9 (GMM) Ferrari's sporting director on Sunday admitted that Felipe Massa retired from the Italian grand prix probably with a rear suspension failure.

The Brazilian, who struck trouble at Monza shortly after banging wheels with Lewis Hamilton, has now fallen 23 points behind the championship leader with just four races to go.

"We still have to look into it more closely," Stefano Domenicali told RTL, "(but) it seems to be probably a problem of the suspension."

Massa's teammate Kimi Raikkonen finished Ferrari's home race just third, telling reporters that despite a sore neck, the F2007 was simply outpaced by McLaren this weekend.

Massa was asked by reporters if he thought emerging as the 2007 world champion was now an impossible task.

"Impossible no, but for sure not easy," he said.

"I'll just keep my head up and be competitive. I'm sure we can fight for more victories."