Robert Kubica has said he has "mixed feelings" following his Renault test, while the team themselves have confirmed it was just a "one-off".
The Pole completed 115 laps in a 2012 Lotus at Valencia on Tuesday, prompting speculation that he could return to the Formula 1 grid on a full-time basis.
But Kubica has admitted that the test proved he has lost something, but it has played an important part in his recovery.
"I would like to thank everybody for making this possible," said Kubica, "I hope it was a good day for everyone and maybe they saw something of my old, 2010 self.
"For me, it has been an important day from an emotional point of view. It has been a long time away from the paddock and I have been through difficult periods, I kept working hard and a few years ago I felt it was impossible.
"I have mixed feelings.
"I am proud with what I achieved , but also it shows what I have lost.
"I don't know what the future will bring, but I know one thing, after working for more than one year to prepare for this, I ran with good pace and consistent in difficult conditions. It is not easy after six years, but I knew I could do the job and I can be satisfied.
"I appreciate the opportunity. Renault gave me my first F1 test in 2005, so I appreciate another test this time around."
Meanwhile, Renault sporting director Alan Permane has stressed that the test was a "one-off" to help give something back to him after seeing his career cut short.
"This was a one-off event for Robert," Permane confirmed.
"His time with Renault was cut short so abruptly and we perceived such a nice future with him.
"The team was in Valencia testing with Sergey Sirotkin, so it was the perfect opportunity to offer Robert a day in the car and contribute in our way to his recovery."