Jenson Button has claimed that his McLaren was "pretty scary to drive" during the Spanish Grand Prix.
The Briton, and teammate Fernando Alonso, again finished outside the points for the team's worst start to a season in recent memory.
However, after a promising build-up to the race in Barcelona, Button has suggested that his car was "unpredictable" for many of the 66 laps at the Circuit de Catalunya.
He told reporters: "My car was pretty scary to drive today - as soon as I touched the throttle, it just snapped away from me.
"It was unpredictable. In low-speed corners, the car was just slow, because I got wheel-spin immediately; in the high-speed stuff, it was just scary, because the rear end would snap away immediately under power.
"I was talking to my engineers for most of the race to try to find out what the root of the problem was, and we switched on quite a lot of handling balance changes to try to cure it. It got a little bit better towards the end of the afternoon, but it was a pretty tough afternoon. Now, we'll thoroughly look at the data and see what the matter was – it's something we've got to look into."
McLaren have yet to score points in any of their first five races in 2015.
