A hydraulic issue with the Ferrari SF-25 forced the team to curtail Lewis Hamilton’s running on the final day of F1 2025 pre-season testing in Bahrain, it has been claimed.

Hamilton split running with Charles Leclerc on the final day of running on Friday, with Hamilton taking over after his team-mate recorded 66 laps and set the fastest lap of the morning session in Sakhir.

Lewis Hamilton test running ended by Ferrari SF-25 hydraulic issue

Additional reporting by Thomas Maher

The seven-time World Champion completed a total of 47 laps and ended the day sixth on the timesheets, 0.800 seconds slower than the pace-setting Mercedes of former team-mate George Russell.

Speaking to media including PlanetF1.com in the press conference during the lunch break, Hamilton confirmed that he planned to carry out a race simulation during his afternoon running.

However, Hamilton returned to the garage with around 40 minutes of the day’s running remaining and did not reappear, with his race run left incomplete.

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In a statement provided to PlanetF1.com, Ferrari confirmed that Hamilton’s running ended early “as a precaution” after the team “spotted an anomaly on the telemetry.”

A report by Italian publication Auto Racer has shed more light on the situation, claiming that a hydraulic issue was the root of Ferrari’s concerns.

It is said that sensor alarms alerted Ferrari to a potential problem with the hydraulic system in the closing stages of Friday’s running.

The sensors was changed, but it proved ‘no false alarm’ – and with the issue ‘no small matter’, Ferrari had ‘no choice’ but to end their day’s program prematurely.

Hamilton’s stoppage means Ferrari completed the sixth-most laps of all in Bahrain with 382 laps in total, one more than reigning Constructors’ Champions McLaren.

Mercedes led the way with 458 laps completed over three days, with Red Bull at the bottom of the pile with 304 laps on the board.

Hamilton hinted that McLaren and Red Bull could prove Ferrari’s closest challengers in F1 2025 after long runs completed by Lando Norris and Max Verstappen caught his eye on Days 2 and 3 respectively.

He told media including PlanetF1.com: “The McLaren did a great run [on Thursday] and I think also Max did a decent one [on Friday].

“It’s hard to know what fuel loads everyone is running, as we’re all doing our own programs, so you have to take everything with a pinch of salt.

“But [McLaren]  won the Constructors’ last year. We expect them to be one of the quickest, if not the quickest, as with Red Bull, who have dominated for many, many years.

“We’ve definitely got some work to do to improve.”

Hamilton went on to declare that F1 2025 testing is the most confident he’s felt about a new season for many years.

Asked to provide his gut feeling on the SF-25’s potential, he replued: “I think that, in the last four years or so, I’ve learned that you really can’t judge too much from the first outlook.

“I definitely think in the past years before that, particularly in the previous generation of cars, it was much easier to know where you stood quite early on with that early feeling.

“I would say this is the most positive feeling that I’ve had in a long time.

“That’s all I can really say for now.”

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Hamilton’s comments come after Alex Brundle, the racing driver and son of Sky F1 pundit Martin Brundle, expressed concern over the behaviour of the SF-25 during Friday’s running.

Commenting on onboard footage of Hamilton’s qualifying simulation, Brundle said: “That Ferrari looks really difficult to drive this afternoon. I was watching it a little earlier on.

“Exit at Turn 4, entry at Turn 11, way wide. Through the mid corner of Turn 13 as well.

“Anywhere where it’s got its tail to the wind, Hamilton is really struggling to get it into the apex.

“This is going to be a better lap for him, but it doesn’t look happy. Big understeer through the mid corner [but] it’s probably one of the better corners of [Hamilton’s] lap.

“It looks really, really nasty behind the [wheel], whatever they’ve done to that Ferrari for Hamilton, whatever they’re testing.

“Of course, you take avenues that don’t always work, but that isn’t friendly.”

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