SAKHIR, Bahrain - Russian teenager Sergey Sirotkin needed bigger shoes as he stepped up for a Formula 1 test with Sauber in Bahrain on Tuesday (April 8) that gave him enough mileage to qualify for a super-licence.The 18-year-old reserve, being prepared by Sauber for a possible F1 future, did 300km and 76 laps - more than a race distance - of the Sakhir circuit that hosted the country's GP on Sunday (April 6).He took it in his stride, posting the eighth fastest time of the 11 drivers present - and best of those who do not have a race seat - with a time of 1min39.023 but he also felt the pinch.'PRETTY PAINFUL'Sirotkin said: "On my fast lap in the morning I made a few mistakes, so I probably lost a second."In the afternoon we had some difficulties with my shoes. They were too small, so it was pretty painful when I was braking. When we changed the shoes, it was still not the best and difficult to drive."Sauber's test engineer Paul Russell said the driver had done well in a car he had never driven before on an unfamiliar layout. "He handled it pretty well. The lap times were very good. He seemed to be learning the car and the track quite well."Sirotkin's compatriot Daniil Kvyat, 19, who races for Toro Rosso, was slowest on the time sheets with 1min40.452; Sunday's race runner-up Nico Rosberg quickest for dominant Mercedes on 1min35.697 after 121 laps.Germany's Nico Hulkenberg was second-fastest for Force India with Ferrari's Fernando Alonso third and Denmark's Kevin Magnussen fourth in a McLaren.McLaren had originally planned for Britain's Oliver Turvey and Belgian Stoffel Vandoorne to test on Tuesday and Wednesday but decided after Sunday's race to keep Magnussen in the car in the interest of continuity.Neither he nor team mate Jenson Button finished Sunday's race.Lotus, which has yet to score a point in 2014 and did little testing pre-season, suffered more problems with its Renault power units and Venezuelan Pastor Maldonado managed only 16 laps. Stay with Wheels24 for the 2014 F1 season – fresh reports every day.