Lesmo, Italy - Triple world champion Jorge Lorenzo could make a wild card comeback to MotoGP after Yamaha signed the Spaniard as a factory test team rider on Thursday.
The 32-year-old retired last year after struggling alongside six-times world champion Marc Marquez in an injury-plagued season at Honda.
Lorenzo won his 2010, 2012 and 2015 titles with Yamaha.
Yamaha said in a statement that Lorenzo would ride the YZR-M1 at this week's MotoGP shakedown test in Sepang, Malaysia, and will also take part in some tests later in the year.
"So far, no wild card rides are planned for Lorenzo in 2020, but Yamaha is open to the possibility, should he decide to race again," the team said.
Yamaha have Spaniard Maverick Vinales and Italian great Valentino Rossi, a nine-times world champion across all categories, as their factory team riders this season.
Rossi, 40, is mulling his options after the team announced on Wednesday that French youngster Fabio Quartararo will be replacing him from 2021.
Lorenzo said he had always planned to stay involved with MotoGP.
"I think this is a suitable role for me. I know the team and the M1 well. The Yamaha really suited my riding style, and it will be very interesting to ’meet up with my old bike again'," he said.
"This allows me to do what I love - riding motorbikes and pushing the limit - whilst enjoying a slightly calmer lifestyle than I did in previous years."
Lorenzo will work with Rossi's former crew chief Silvano Galbusera in the test team.