Leading 125cc and 250cc team Aspar will make its long-awaited MotoGP move with Ducati next season.
Jorge Martinez's team will run a single Ducati, with 250cc frontrunner Alvaro Bautista tipped as favourite to take the seat.
"Still not sure who the rider is," Ducati boss Livio Suppo told AUTOSPORT. "The priority is Alvaro [Bautista]. I like him a lot since last year. There is no secret about that. If it won't be him then we will see."
The squad was previously linked to a programme with Kawasaki, before that fell through last winter.
Ducati now has the capacity to run an additional satellite bike after the recent closure of the Hernando team that had run Sete Gibernau.
"We want to do five bikes, no more," said Suppo. "We are structured to do five. We are trying to do a programme with five riders.
"One thing we know, in the teams there is not such a big difference between the factory bigs and the satellite bikes. Also in terms of how we manage it. [Mika] Kallio, for example, has a Ducati Corse engineer and electronic technician.
"We treat all the teams the same. We are two small to run two programmes, one for the factory and one for the others. We treat all the same. We think with these kind of bikes it is better to have direct control and it works."