Lewis Hamilton eighth as Fernando Alonso top times in China
Ferrari's Fernando Alonso welcomed his new team principal to Formula 1 by setting the pace in first practice at the Chinese Grand Prix.
Observed by Marco Mattiacci, drafted in following Stefano Domenicali's resignation, the Spaniard beat Mercedes driver Nico Rosberg by 0.398 seconds.
The other Ferrari of Kimi Raikkonen failed to set a time, suffering a power steering problem.
McLaren's Jenson Button was fourth and Mercedes' Lewis Hamilton eighth.
Hamilton's session was curtailed when a suspension problem forced the team to stop his running with about 20 minutes to go to get the car fixed for second practice, which starts at 07:00 BST.
Red Bull's Daniel Ricciardo was third, 0.989secs slower than Alonso, ahead of McLaren's Jenson Button, Force India's Nico Hulkenberg, McLaren's Kevin Magnussen, the Toro Rosso of Jean-Eric Vergne and Hamilton.
Red Bull's Sebastian Vettel, the world champion, and Williams' Felipe Massa completed the top 10.
Rosberg, Vettel and Sauber's Esteban Gutierrez all had brief off-track moments during the session, without major incident, as the drivers struggled to get the tyres working in the cool ambient temperature.
Toro Rosso's Daniil Kvyat had a spin towards the end of the session after misjudging the entry to the Turn 14 hairpin at the end of the long back straight.
Raikkonen's car spent almost the entire session up on jacks in the garage after the Finn completed an installation lap.
Raikkonen is notoriously sensitive to the feel of his steering.
Mattiacci - formerly head of Ferrari's road car operation in North America - spent the session watching proceedings, in sunglasses despite the cloudy weather, clipboard in hand, as he began to get to grips with the complexities of F1.
Alonso was able to complete a full programme, but his pace is unlikely to be an accurate representation of form for the weekend.
Mercedes have had an advantage of about a second a lap in the first three races of the season, and all the drivers acknowledge that is unlikely to have changed in the 12 days since the last race in Bahrain.