A driver accused of causing a fatal crash had been seen tailgating and travelling "too fast" before the head on collision, a court heard.
Dr Darran Venn died when his car collided with a BMW 5 Series driven by John Joe Darch, 25, on the B3157 near Weymouth on 17 May 2017.
Mr Darch's car was "completely" in the opposing carriageway, Bournemouth Crown Court heard.
He denies causing death by dangerous driving.
Prosecuting, Charles Gabb QC said there was heavy rain and mist at the time of the crash at 08:30 BST and that Dr Venn, an engineering specialist, "didn't stand a chance".
Another driver had reported Mr Darch "tailgating her ... pushing her to go faster" shortly before the crash and another said he was "going far too fast".
Mr Gabb told jurors Dr Venn had been driving "absolutely perfectly" when he was hit.
He told the court Mr Darch, of Ranelagh Road, Weymouth, later told police he "knew the road like the back of his hand" and was aware of its dangers.
"This crash was caused entirely by the driving of the defendant - completely and utterly," he said.
"The BMW was completely in the opposing carriageway in the path of Dr Venn."
Investigators were unable to work out the exact speed Mr Darch had been driving at.
The court also heard one of Mr Darch's tyres was worn to a "dangerous" level.
The trial continues.