Fernando Alonso has repeated his claim that he is not planning to return to formula one.
However, since the Spaniard quit the sport last November, he has also not ruled out a comeback.
In Bahrain, after just a four month break from the F1 cockpit, Alonso was back at the wheel of a McLaren on Tuesday for the post-grand prix test.
"The team has taken a step forward in all areas," he said afterwards.
"The engine is also better, so I think with this car it is possible for McLaren to be the leader of the middle group of teams."
Two-time champion Alonso, however, denied that the test is the first step in a 2020 comeback.
"Actually no," he said.
"I have achieved everything I dreamed of in formula one and even more and I have no regrets.
"If I ever come back to formula one, which I doubt because I made a firm decision to complete this stage of my career, then it is only if I have the opportunity to fight for the world championship.
"I think no driver would refuse such an opportunity, but the idea of being seventh, sixth or even fourth does not interest me," Alonso, 37, added.
Alonso, who famously raced for the 2006 title against Michael Schumacher, also commented on the debut on Tuesday of the F1 legend's son Mick.
"In my view he has to use this opportunity, because you never know when it will be your turn to come to formula one," he said.
"I think this year Mick is prioritising Formula 2, and it will not be easy for him because there are some great drivers with great experience.
"But if he succeeds, then some of the F1 teams will believe in his talent and he will get a ticket to the world championship," Alonso predicted.