Fernando Alonso was forced back into the McLaren garage after just a single installation lap this morning, with Honda diagnosing an issue with the engine's oil system.
The problem is apparently located at the front of the V6 hybrid power unit which would require a proper dismantling of the engine in order to further investigate the issue.
"We have an oil systems issue which requires a full investigation," said a Honda spokesperson.
"We plan to run again today, but due to the difficult access location it will take several hours to resolve."
Red Bull's RB13, with Daniel Ricciardo behind the wheel, also had a troublesome debut with the car stopping out on the track after a handful a laps, halted by a benign sensor issue, and bringing the red flag.
Red Bull is expected to rejoin the session shortly however.
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