Michael Schumacher got off to a promising start in his bid to win his third straight Formula One race and close in on defending champion and points leader Fernando Alonso.
Schumacher sat out the first practice on Friday for the German Grand Prix, then drove his Ferrari to the fastest lap among race drivers in the second session.
Alonso, third among race drivers in the morning session, was only 15th in the second trial.
"This quite a short lap and there seemed to be a lot of traffic out there today," Alonso said. "My timed laps were all compromised a little bit by this."
After 11 of 18 races, the Spaniard has 96 points and Schumacher has 79. A win is worth 10 points.
Schumacher, though, is riding a two-race winning run. A hat trick at the German Grand Prix on Sunday would see him further reduce Alonso's lead at the top of the Formula One drivers' championship.
Schumacher's straight wins in the United States and France snapped Alonso's four-race streak. The Renault driver has won six races so far this season and has only one finish outside the top two. Schumacher has four wins.
No car apart from Renault or Ferrari has won a race this season, with one victory going to Alonso's teammate Giancarlo Fisichella. A shower dampened the track shortly before the second session, making it slippery, Alonso said.
"The most important thing, though, was to recognize that the conditions today were quite different to what we expect for the rest of the weekend," Alonso said.
BMW-Sauber test driver Robert Kubica used his only day of action this weekend to complete the fastest lap of the day of 1 minute, 16.225 seconds, .277 seconds ahead of Schumacher. Test drivers are only allowed to race on the practice day Friday.
Schumacher is Formula One's most successful driver with 88 career victories. The seven-time champion has three wins in Hockenheim. Kimi Raikkonen gave McLaren-Mercedes a boost by coming in fourth, behind another test driver, Robert Doornbos in a Red Bull. Felipe Massa, the second Ferrari driver, was fifth.
Super Aguri, rebuked by stewards for using illegal tire warmers in the morning, gave the team's new car its debut, but only Takuma Sato set a time in second practice.
New race driver Sakon Yamamoto suffered technical problems and did not record a flying lap, while Sato was the last. The weather cooled off after a major heat wave, but Friday's track temperature was still 36 degrees C (96 degrees F), although way down from 50 C (122 F) a day earlier.