Daniel Ricciardo left Japan "unsatisfied" after a drive-through penalty dented his hopes of scoring points.
Having started 16th on the grid at Suzuka, the Toro Rosso driver was looking good to finish in the top 10 until he passed Adrian Sutil at 130R. He went off the track while trying to get overtake the Force India and, because he didn't give the place back, he was handed a penalty.
He ended up finishing down in 13th place and admits he was "surprised" by the decision to hand him the drive-through.
"Sometimes the whole weekend revolves around just one decision. I'm fairly sure without collecting a drive-through penalty I'd be leaving Suzuka with a good haul of points and feeling deeply satisfied with our weekend's work. Instead I'm leaving... well, let's say unsatisfied," he wrote on his official blog on the Toro Rosso website.
"I was and am genuinely surprised that the stewards penalised me for the pass on Sutil. When my engineer told me I'd picked up a penalty, it never crossed my mind it was for that. Earlier in the race when I was out-of-sequence on the hard tyre I'd collected a big train of cars behind me so I thought perhaps I'd done something dirty then.
"I thought possibly I'd weaved when I was defending from [Nico] Hulkenberg, or maybe cut him off without noticing. I didn't think I had but it's difficult to judge with the mirrors. When I heard what it was actually for... as I say, surprised.
"Moving on, if you can disregard the eventual result - believe me, right now that's difficult - I had a really good day. In Korea last week I don't think I could've done a better job and it's much the same here. I think we maximised the potential of what we had this weekend and I'm very pleased with the way I drove."