User blog comment:Jkphantom9/RWBY clip on Lazer Team Livestream/@comment-11188061-20140622040640/@comment-9090085-20140622162324

Is it?

Don't forget that Mercury is one of the main fighters for the villeins, and Pyrrha is thought of as "the strongest fighter"(who we know is at her best fighting people with her semblance); a "friendly" tournament fight would be a good opportunity to demonstrate just how much stronger Mercury is compared to our heroes by defeating Pyrrha one-on-one. (in the same way that Roman's fight with Blake and Sun showed that he couldn't be beaten 1-on-1)

On the other hand, he has already shown just how formidable he is by overpowering Pyrrha with pure physical ability - no semblance, no weapons - and him "losing" while clearly holding back when Pyrrha is going all out would still show just how strong he is. Heck, might even still serve the purpose of rocking Pyrrha's boat: defeating your opponent  when you're both at you best is one thing, but winning because your opponent let you win, that might be subtly disturbing to Pyrrha.

On that note, I wonder if that's why Emerald is watching so intently - she's curious not just as to how strong her potential foes are, but also how far Mercury is going to go in his fight.