By James Caldwell, PWTorch assistant editor

The Big Four matches for next year's WrestleMania (April 7, 2013) are beginning to take shape, according to a Wrestling Observer report, but one man missing from the equation is off-air star Brock Lesnar. Along with John Cena and The Rock, Lesnar is one of three top stars featured in Mania advertising.

Right now, the rough-draft, subject-to-change Big Four line-up looks like:

- The Rock vs. John Cena in a Mania re-match (likely for the WWE Title).

- C.M. Punk vs. The Undertaker, who the Observer says is working Mania and Punk "would be his most likely opponent."

- Ryback vs. Big Show, which is currently at the discussion stage, but the current booking points to a big-man encounter.

- Sheamus vs. Randy Orton, which could be Smackdown's top match after WWE held off on a Sheamus-Orton feud throughout 2012.

Caldwell's Analysis: Where Brock Lesnar fits in remains to be seen, but WWE could always book a Lesnar vs. Triple H re-match and create a Big Five this year. Lesnar has been off TV since beating Triple H at Summerslam, and since then, Paul Heyman has associated with C.M. Punk, Ryback has transformed into a featured act, and The Shield has debuted in a loosely-affiliated relationship with Punk and Heyman. It could all lead to Hunter and Lesnar simultaneously returning to TV as part of the angle and set up a re-match with an added stipulation.

There's also the Dolph Ziggler and Zack Ryder factor. Their Mania match has unofficially been set for months and Ziggler said in a recent interview that he wants to honor the match, but the two men are going in opposite directions. Ziggler is working with WWE's top star, John Cena, and Ryder has returned to a comedy tag team act with Santino. Of course, Ziggler would be squeezed out of a headline Mania match in the above Big Four/Five scenario, but the X-Factor is his Money in the Bank briefcase.

With nearly 2,000 votes cast, PWTorch readers are most-predicted WM29 as the place where Ziggler cashes in his World Title MITB briefcase. Ziggler could always beat Ryder early in the card, then cash in his MITB briefcase after the World Title match later in the PPV to make a big splash on the biggest stage of the year. Of course, Ziggler could cash in before Mania and then all bets are off for Smackdown's World Title match, especially factoring in the Elimination Chamber PPV in-between the Rumble and Mania.

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