Why it makes sense: Jony's principal weapon is speed, but even with Marcelino's focus on speed, he didn't fit into our plans. With the success of players like Vietto and Gerard, he's not needed as a second striker.
And, to be honest, Jony has shown he's really not an everyday Primera player, but can do beter in the Segunda. Valladolid are looking for scoring punch.
Why it might not happen: Money. Jony's salary is €800k yearly, some of which we are paying apparently since Rayo are so skint. His market value is variously estimated at €2-2.5 million, and I doubt Valladolid can pay anything like that, or his current salary (Marca says we are trying to negotiate it down). He's under contract until June 2017, so is it worth taking a hit on the transfer fee now in order to save us paying out salary to someone we don't really need?