In a recent interview about making 14 blades, Donnie Yen spoke about the fact that they are currently in talks with Tony Jaa over a future movie. After the success of the Ong bak series and Warrior King, Jaa has caught the eye of many Hong Kong directors and fellow martial art stars, Donnie Yen being the latest.
Taken from the wujing.org website this small part of the interview suggests that this will happen sooner rather than later.

Heard that you’re collaborating with Tony Jaa and there would have a decisive showdown?
Donnie Yen: Indeed, there’s such a plan, director Stanley Tong and Raymond Wong are helping me invite Tony Jaa, I hope they’ll succeed, but can’t divulge the details.

With Donnie Yens new take on kung fu cinema, bringing ufc style moves to the big screen (Sha Po Lang, Flash Point) and working very well, Jaa’s style of martial arts will fit perfectly in a yen film. So who will end up the winner? Either way i think it’ll work fantastic on screen and very much hope it happens.