Wolff worried by repeated 'open heart surgery' performed on W10

Mercedes has enjoyed a flawless reliability record so far this season on race day, but recent issues that required some big interventions did not escape Toto Wolff's attention.

The Silver Arrows outfit's 100 percent winning track record in 2019 is first and foremost rooted in the outstanding endurance of its W10.

However, a hydraulic leak in Canada discovered after qualifying on Lewis Hamilton's car and a sensor issue on the Brit's W10 detected in free practice in France offered a clear reminder to Wolff that failure is perhaps just one small component away.

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In both instances, repair work forced Mercedes' crews to dig deep into their car's inner workings.

"Our result in last year's Austrian Grand Prix was the low point of the 2018 season," said the Mercedes boss ahead of next weekend's race in Spielberg.

"A double DNF after a promising front-row lockout meant that we left a lot of points on the table.

The race was a cruel reminder how quickly things can go wrong in our sport and that reliability and performance go hand in hand in Formula One.

"This year, our race finishing record has been good, but it would be complacent to ignore the fact that for two weekends in a row now, our mechanics had to perform the equivalent of "open-heart surgery" on our cars.

"We've faced a number of different issues on different components, each of which could have easily caused us to retire, so we need to get on top of those challenges as quickly as possible."

Mercedes will work to keep its reliability in check in Austria but Wolff also points to next weekend's predicted high temperatures as a potential source of concern.

"The forecast for Austria predicts temperatures of 30 degrees Celsius and more - combined with the reduced air density owing to the track's location at altitude, this means that cooling could become a real challenge in Spielberg.

"Add to that the short lap and the close gaps on that circuit and our direction is clear: we need to keep working diligently, stay humble and give it everything to do a better job than we managed 12 months ago."

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