Former F1 driver Mika Salo has admitted he is worried about the flagging form of his fellow Finn Valtteri Bottas.

With his new beard on show after a lacklustre 2018, Bottas came out of the box with surprisingly strong form early this year.

But more recently he has slipped behind Lewis Hamilton once again, and now trails his Mercedes teammate in the drivers' championship by 29 points.

And Salo says Bottas' pace in Canada was "really strange".

"Just not fast enough," the former Ferrari driver and current FIA steward told C More broadcaster.

"He did not get past the slower cars and his pace was never good. It even seemed like he was saving the tyres. He drove so easily," said Salo.

"That's now two pretty bad losses to Hamilton in a row, in Monaco and Canada," he added. "The points different is going up. Yes, I think he needs to start driving a bit more at the edge."