Bahrain's Sakhir circuit has filled troublesome drains with concrete and carried out additional welding work ahead of Saturday's season opener after loose covers halted Formula One testing last week.
The governing FIA said in a note on Wednesday that remedial works had been carried out around turns seven and 11, with welding at certain areas around the track.
- Unlapped: How to listen or watch ESPN's F1 show
Red Bull's Max Verstappen said last week that more checks were needed after testing was halted two days in a row amid fears the latest high-downforce cars were making such incidents more likely with their aerodynamic suction.
"Maybe these kind of things can be checked a bit more," Verstappen said. "We know that this is a potential problem with these cars and when you go to certain tracks you know where the drain covers are."
The separate incidents revived memories of a more serious one that caused considerable and costly damage to Carlos Sainz's Ferrari during practice for last November's inaugural Las Vegas Grand Prix.
