Mercedes is reportedly keeping an eye on Max Verstappen, ready to pounce on the Dutch driver if Red Bull Racing fails to live up to its driver's expectations.
In light of Honda's significant progress over the winter, which has been verified on the track, Red Bull motorsport boss Helmut Marko went on record to predict race wins and possibly a world title for the Milton Keynes-based outfit and its star driver.
However, the start of the season revealed Red Bull's deficit relative to Ferrari and Mercedes, with its weakness linked to the aerodynamics of its RB15 chassis.
"In Bahrain we identified a weakness in the aerodynamics," said Marko after this week's in-season test in Bahrain;
"We think we know the cause and have already implemented amendments. Verstappen's time on Tuesday was quite okay.
"It's not a conceptual problem, but a detail thing – and it's not for the first time it has happened. But the wind in Bahrain multiplied it."
Red Bull hopes to solve its downforce issues for Barcelona at the latest. But sustained under-performance this season could unsettle Verstappen and perhaps entice the 21-year-old to question his future with Red Bull.
©RedBull
While Verstappen is contracted to his team until the end of 2020, a performance clause allows the driver to exercise a right to leave Red Bull.
That eventuality hasn't been lost on Mercedes according to Marko.
"Toto Wolff has called him and his father Jos repeatedly in the past months," Marko told Germany's Auto Bild.
"But I'm relaxed, the performance clause in Max's contract should be safe and he feels comfortable with us.
"If we provide him with championship-worthy material, I'm not worried, he'll stay."
Gallery: The beautiful wives and girlfriends of F1 drivers
Keep up to date with all the F1 news via Facebook and Twitter
