Pascal Wehrlein expressed his happiness after he received test outings with both Force India and Mercedes at the Circuit de Barcelona-Catalunya on Thursday.
Wehrlein was called up by Mercedes to replace the unwell Lewis Hamilton and after sampling Force India's 2014 car, he switched to Mercedes' 2015 machine for the afternoon session.
Wehrlein's time of 1:28.329, set during his stint in the Force India, left him in eighth place on the leaderboard.
"Today was a really good day in my career," he said. "I was quite surprised in the morning when I got the information that I would be driving the Mercedes in the afternoon.
"But I am here and I want to drive, so I am ready for any opportunity. To drive two Formula One cars in one day was amazing, so I'm very happy.
"We lost a bit of time in the garage which was a shame as I would have liked to do some more laps. But the time I had I really enjoyed. Spending the morning with Force India, also, was a great experience.
"It's a good team, everyone was really welcoming and after a few laps I felt very confident in the car."
Wehrlein will return to duties on Saturday when he resumes testing with Force India.
