BMWs championship-challenging driver spun out on the entry to the stadium section after completing just eight laps in the damp morning session, crashing into a tyre barrier and damaging the left-side of his F1.08.
But after completing 36 laps in the afternoons dry running, setting the eighth fastest time, the Pole believes his weekend is still on schedule – although he says he is hoping the team can improve the balance of his car.
“We tested the tyre compounds and did some basic set-up work,” he said.
“Unfortunately, this morning I touched the white line with the grooved tyres.
“There was some standing water. I lost control of the car and hit the barrier.
“However, we did not miss a lot of running time in the dry.
“This afternoon we were more or less able to complete the programme as planned.
“We now have to analyse the data and improve the balance of the car.”
His team-mate Nick Heidfeld enjoyed a far more straightforward opening day to his home grand prix, setting the eighth and ninth fastest times respectively in both sessions.
He was pleased with the progress the team has made with the set-up of its car around the medium downforce Hockenheim since last weeks test.
“Compared to last weeks test the cars balance was better today,” he said.
“We have made several changes during the practice sessions and completed the tyre comparison.
“After wet conditions this morning, we knew there was a chance of more rain at the end of the second session.
“Consequently we switched to soft tyres earlier than usual.
“Overall both sessions went quite well.”