Mechanical gremlins cost the Force India rookie Paul di Resta valuable set-up time ahead of Sunday's Chinese Grand Prix.
Di Resta, who turns 25 on Saturday, arrived in Shanghai this week buoyed by the prospect of finally getting a full Friday programme under his belt after giving up his car to reserve driver Nico Hulkenberg in first practice in both Australia and Malaysia.
The Scot completed the morning session in 15th place after recovering from an early spin, but trouble struck when his car developed a fuel pressure problem which ruled him out of the second 90-minute session.
Di Resta has so far been adept at maximising his performance after limited Friday running, claiming points in both Melbourne and Sepang with back-to-back 10th-placed finishes.
But the second practice session is generally when teams hone their cars by focusing on qualifying and race simulation work, and Di Resta admits the time lost today represents a significant blow.
"We got a little bit of an idea of where the car was in FP1, but obviously it's crucial to try and take part in FP2," said Di Resta.
"I think that I am a little more disadvantaged than I have been at any other grand prix now because effectively I have lost three sets of tyres and the important part where you try to do a bit of qualifying and race simulation.
"The guys are working hard, so hopefully we can catch up on some lost ground tomorrow morning."
Di Resta also experienced KERS issues during the morning session, but on the plus side managed to successfully evaluate the team's latest aerodynamic update.
His bosses remain confident they can use Saturday morning's final practice session to make up for the setbacks.
"We found a fuel pressure problem with Paul's car, and despite the team's best efforts to resolve it we were unable to get the car back on track in the time available," the team's circuit engineering director Dominic Harlow explained.
"The cars are increasingly complex now with the extra systems on board, and the work involved to complete the job was too much.
"It was frustrating, but the issue is now eliminated and we will make up for the lost track time as best as possible."
