The two-time world winner walked off from grand prix racing by the ending of their 2018 season however has turned into a McLaren ambassador and adviser for 20-19.
In announcing his new character, the team said he would drive the 20-19 car to help its development for this particular year and 2020.
He will get a whole day of running Tuesday but will sit out Wednesday morning regular race driver Carlos Sainz Jr may drive, until returning to the course in the day.
Sainz will also push Tuesday morning in the car McLaren is free to run because it pleases, together with team mate Lando Norris carrying over that car on Tuesday day and driving for the entire day on Wednesday.
By committing Norris and Sainz to Tuesday and Wednesday running in the car it’s set up freedom over, McLaren has secured itself in to running a ‘rookie’ driver in the next evaluation in Spain.
One of both days at Barcelona following the Spanish Grand Prix will need to be conducted by means of a driver who has not started more than two grands prix.
Norris will meet that criteria next week since Bahrain will just be his next F1 race.
This means Bahrain may well not be Alonso’s just chance to get behind the wheel of their MCL34 during the entire year.
He may also drive again if Pirelli conducts a second two-day evaluation in Abu Dhabi after the season finale.