Toro Rosso boss Franz Tost has labeled Max Verstappen's performance in the Monaco Grand Prix so far as "extraordinary".
The 17-year-old rookie finished in second place in the opening practice session – behind reigning world champion Lewis Hamilton – despite it being his first time driving around the Monte Carlo circuit.
Verstappen, the youngest driver in F1 history, completed a strong day with the seventh fastest time in the afternoon.
"We know Max is a very, very highly skilled driver," said Tost. "I was impressed by how he achieved this really, really good time in P1.
"He went out in the morning and from run to run he improved his laptime without making any mistakes.
"His car control and his feedback, it was really, really extraordinary.
"I am very happy that he is in the team."
Tost, whose team has enjoyed a strong start to the season, is not ruling out a podium finish if rain hits the track during Sunday's race.
"We must be realistic," he added.
"There are teams in front of us who have double the budget and a competitive badge and it is not easy to compete against them but we have two drivers, and also a car which is quite competitive and maybe with special weather conditions, maybe if it is raining, to help us to bring of the drivers to the podium."
Red Bull team principal Christian Horner admitted he was also impressed by Verstappen.
"I thought it was super," said Horner. "For a guy that can't rent a hire car yet it is enormously impressive.
"The two Toro Rosso drivers have done a wonderful job this year. It is one of the positive stories in F1."