Renault's Nico Hulkenberg was left scratching his head after Thursday afternoon's free practice run in Monaco, baffled by his RS17's lack of balance.
After an electronics issue in the morning session deprived the German of mileage, Hulkenberg ran consistently in FP2 albeit considerably off his expected pace, and without a clue why.
"I don't know, I can't tell you at this moment. I'm scratching my head as well," he said, ending the day all the way down in P17.
"I'm a bit surprised with the car and a balance that I found and the grip in P2, which is very poor and far away from what I expected it to be.
"So we need to really investigate what's going on, because I'm sure something is not right. It felt really poor out there, not just that I'm struggling with the balance a lot and confidence in the car, but also the grip from the tyres what we get seems really odd and poor.
"It's far from ideal that we missed P1, because now we are like one step behind or two steps behind, because had we found that out in the morning we could have reacted already big time before P2, trying to fight it. We did not have that opportunity, so it's going to be difficult."
Hulkenberg's problems appeared to surface at the outset.
"Straight from first run I felt like I'm not going anywhere," he admitted.
"I wasn't even looking at my lap times initially, because I know they were terrible. You feel its just not there.
"Tricky day, so a bit of a challenge ahead of us."
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