Button's grid penalty adds up to 70 place drop

By Alan Baldwin MEXICO CITY (Reuters) - Jenson Button faces a record but meaningless 70 place grid penalty at the Mexican Formula One Grand Prix after problems with his McLaren's Honda power unit forced him to sit out Saturday's qualifying. The impossible sanction, given that there are only 20 cars on the grid, will translate to the 2009 world champion starting last. Button, whose tally was confirmed by the team after he said he had no idea what it amounted to, was frustrated nonetheless with what has become a painfully familiar situation. "We all get frustrated when things don't go our way," said the Briton. "I wanted to qualify today even though I'm going to start last tomorrow whatever. "I still want to go out in qualifying and do my best. It's a real challenge, it's great pushing the car to the limit on low fuel, new tyres. We didn't have that opportunity today but it happens. "I'd rather see improvements like we have from the new spec of engine and have a few issues of a race weekend because it's all promising for the future," he added. Honda motorsport head Yasuhisa Arai said the latest problem, which surfaced in final practice, was a sensor signal failure that was still being analysed. With Button's team mate Fernando Alonso collecting a 10 place penalty and Ferrari's Kimi Raikkonen five for a gearbox change, the Mexico grid will see three former champions lining up at the back. Marussia's Will Stevens said that would be a strange feeling, if a short-lived one. "We've got so long down to the first corner, so if I'm honest I don't expect them to be behind us before the first corner," he said. "Our starts have been really good but they take off and leave us in the distance. I imagine I will be following (team mate) Alex (Rossi) into turn one and those guys will be in front of us by then." (Reporting by Alan Baldwin, editing by Gene Cherr)