(CNN) -- Venezuelan Pastor Maldonaldo was fastest in a rain hit second practice session at the German grand prix. In Friday's dryer first session, McLaren's Jenson Button led teammate Lewis Hamilton at the top of the time sheets.
Seven-time champion Michael Schumacher had a day to forget at Hockenheim, crashing his Mercedes into a wall in the final few minutes of the second session.
The German driver, known for his ability to handle wet track conditions, had been going well at his home race.
"The way I ended the second session was obviously not part of the plan," Schumacher told the official website.
"I simply slid off track because I lost a little concentration, we were talking on the radio and I was altering some settings at the same time.
"Overall the session went ok. I think that qualifying will probably be wet tomorrow, so today's weather was useful in that respect."
The Mercedes team suffered a miserable end to the day as it was confirmed that Schumacher's teammate Nico Rosberg will start five places back from his qualifying position as punishment for replacing his gearbox.
Defending World Champion Sebastien Vettel enjoyed a much improved second session. The German moved from twelfth in the morning to third in the afternoon.
"We just got used to the conditions, as there may be rain tomorrow and also on Sunday. The forecast isn't looking great," he told the Formula 1 website.
Vettel's Red Bull teammate Mark Webber described the conditions as "unreal", as he endured a mixed day.
"We didn't expect the rain to be this bad today, but it was quite heavy at times - we even used the extreme full wet tire," the Australian, who won the previous grand prix at Silverstone, told the official website.
"That's two races in a row now with tricky conditions."
Current championship leader Fernando Alonso was happy with the way his car handled the conditions. The Ferrari driver, who has won two races this season declared himself "pleased with how things went."
"The car behaved well in all conditions, which is always a good thing and we were also able to see how the various types of tire worked."
McLaren unveiled a number of upgrades to their car as they attempt to rescue a disappointing season. Former world champions Button and Hamilton rewarded their team's efforts with a good first practice session.
"The men and women back at the factory did an incredible job to get all the upgrades to the track this weekend. It's definitely a step forward," Hamilton told the official website.
"The car doesn't feel bad at all. It's tough in the wet out there, like driving around on an ice rink, but I feel positive that we can do something good this weekend."
Button echoed Hamilton's comments, as he declared to the official website that the team can be happy with the new parts, "most of them worked correctly - so it's nice to see the improvement. I want to say a big 'well done' to the guys at the factory."
The weather forecast suggests the track will be damp for qualifying tomorrow, with similar conditions likely for the race on Sunday.