Toto Wolff has indicated Valtteri Bottas needs to put his foot back down on the throttle.
After a bad 2018, Bottas emerged this year with a new look, a new attitude and impressive new form.
But as the season reaches its mid-way point, Bottas is once again showing signs of slumping against a resurgent Lewis Hamilton and rumours Esteban Ocon could take his place for 2020.
"Is he feeling the pressure from Lewis? I hope not, even if in the duel with Leclerc he slept a little bit," Mercedes team boss Wolff is quoted at Paul Ricard by Sky Italia.
Bottas was notably despondent after the French GP, admitting the performance gap to Hamilton was too big.
But the Finn insisted: "He’s not unbeatable, I know that. I just need to work hard."