Ocon's Mercedes engine survives for Monaco

Ocon was on course to score points in the Spanish GP before a poor pitstop made him drop down the order. Later on, his Force India released a trail of smoke and came to a halt on track.

Force India was not sure of the problem after the race but the nature of the stoppage and the team's report that it deposited a lot of oil suggested it could be an internal combustion engine failure.

However, the problem has instead been traced to an oil system failure, and the software protection in place is believed to have prevented engine damage.

That means Ocon should be able to continue with the engine in Monaco for a sixth GP weekend of the season.

This would keep him in line with a regular penalty-free programme of only using three combustion engines for the 21-race season.

It means Mercedes is still the only engine manufacturer yet to have a unit shelved this year.

Red Bull's Daniel Ricciardo suffered a spectacular Renault failure in China, while Toro Rosso gave Brendon Hartley a complete set of new Honda components after his Spanish GP practice crash.

Hartley's change came after Ferrari swapped out Kimi Raikkonen's engine following Friday practice.

Raikkonen suffered another engine-related problem in the race but like Ocon should avoid a change for this weekend's race in Monaco.