WWE Hell in a Cell 2015 comes at us tomorrow night, live on the WWE Network (or PPV if you've not yet worked out that it's much cheaper to order via WWE's own streaming service) and while ratings may be sagging and creative are on autopilot, there's every chance that this could turn out to be a very good show. Although Undertaker and Brock Lesnar's rubber match is undoubtedly the main attraction, John Cena's United States Championship open challenge could easily be the best bout of the evening, considering the role that Cena's been on this year. Of course, that depends to some extent on who Cena's opponent is, which is a mystery at present. Let's take a look at some of the candidates. Daniel Bryan A long shot, perhaps, since WWE doctors still haven't cleared him (despite his own doctors having done so some time ago). Bryan would make sense, given his history with Cena and the fact that he had to relinquish the Intercontinental Title due to injury - could he becoming back to reclaim gold in his return? Tyler Breeze Prince Pretty only debuted on Smackdow, erm, yesterday, but he's already set about making an immediate impact in WWE. Attacking Dolph Ziggler and aligning himself with Summer Rae was a good start, but stepping up Cena on PPV would really make a statement of intent. Finn Balor Balor should have really been called up to the main roster some time ago, but you get the feeling they're saving the talented Irishman's debut for something really special. Could the NXT Champion unleash the demon on the current US Champion? It would be a helluva match, and a helluva debut, if Balor was to answer the call at Hell in a Cell. Kevin Owens Owens and Cena have fought many times this year already, including three PPV singles matches. Do they really need another? Well, considering how awesome their first three matches together were, it's unlikely anyone will be complaining if Owens answers the challenge. Don't get your hopes up, though... Dolph Ziggler Ziggler and Cena fought over the US Title on Raw two weeks ago. That was a great match. If they fought on Sunday, it would be a great match. Beyond that, it's difficult to see WWE going with Dolph, even though he is very much in the running. Time for a full-blown heel turn, perhaps? Neville The Man That Gravity Forgot has been the Man That WWE Creative Forgot lately, his momentum stalling since teaming up with Stephen Amell at SummerSlam. It's been a couple of pre-shows in a row for the talented Geordie, who could really use some direction. A big match against Cena, and potential US Title win, would give him just that. Carlito Carlito has been rumoured to have been in negotiations with WWE over a return in recent weeks. Cena's open challenge would provide him with the perfect stage to waltz back into the limelight and it makes sense from a storyline perspective - Carlito won the US Title from Cena in his Smackdown debut match 11 years ago. A long shot, but definitely a possibility.