Valentino Rossi’s imminent return to Yamaha – to be announced on Friday morning, Yamaha and Ducati having been forced to move the schedule forward once news of the switch leaked – will accelerate the final movements in MotoGP’s silly season, with the remaining open grid slots on prototype machines likely to be filled in very short order once the Rossi announcement has been made. Rossi’s return to Yamaha will be heralded much as his departure for fresher pastures at Ducati was, only this time the roles will be reversed.

First, Ducati will issue a release thanking Valentino Rossi for his time with the factory, and shortly after – minutes, rather than hours, – Yamaha will issue a press release welcoming Rossi back to the fold. The difference, perhaps, is that this time a love letter such as the one Rossi wrote to Yamaha after he left in the middle of 2010 is unlikely to be forthcoming.

With Rossi at Yamaha, that leaves five prototype seats still open: The factory Ducati left vacant by Rossi’s switch to Yamaha; the as-yet unfilled second Monster Tech 3 Yamaha seat (the first seat is for Bradley Smith, who will be moving up from Moto2 as provided for in the contract he signed with Herve Poncharal in the middle of last season); the San Carlo Gresini Honda bike currently being ridden by Alvaro Bautista; and the Ducati junior team seats, in a yet-to-be-decided structure with one or more yet-to-be-selected teams. So who will be filling those seats? And where does that leave the riders left standing once the music stops?