SummerSlam is one of the biggest pay-per-views on the WWE calendar, and this year’s event is shaping up to be very unpredictable. With the summer’s most important show just two months away, WWE could go a number of ways with the biggest matches on the card.

Seth Rollins has been the WWE World Heavyweight Champion since WrestleMania 31, but Brock Lesnar’s return puts his title reign in jeopardy. All three former members of The Shield have been involved in the title picture over the past few months, and each could have a big match on Aug. 23 at Barclays Center.

The last two SummerSlams featured a few of the most important moments in WWE in recent years, and the same might happen this year. At SummerSlam 2013, Daniel Bryan won the WWE title for the first time, only to lose it minutes later. Lesnar beat John Cena at SummerSlam 2014 in one of the most-one sided main events in WWE PPV history.

It’s unclear in what direction superstars like Neville, Dolph Ziggler and King Barrett are headed, but educated guesses can be made regarding much of the main roster. Below are predictions for the SummerSlam 2015 match card.

Brock Lesnar vs. Seth Rollins (WWE World Heavyweight Championship Match)

There have been a lot of rumors surrounding what WWE will do with Rollins in the near future. Many of them concern a babyface turn and a possible match with Triple H. While a change in the champ’s character could be coming soon, it doesn’t make much sense for it to happen yet, since he’s been the company’s best heel for the last year. Lesnar and Rollins are set to have a championship match at Battleground on July 19, and there has been speculation that Lesnar could become the champ and face Reigns at SummerSlam. But it appears that Reigns is headed in a different direction, and a Lesnar-Rollins rematch makes the most sense for the main event.

John Cena vs. Kevin Owens (United States Championship Match)

Cena vs. Owens is quickly shaping up to be the best feud of 2015. After Owens beat Cena cleanly in his first match on the main roster, Cena won the rematch at Money in the Bank in what was one of the best matches this year. Owens said on “Monday Night Raw” that he wants to fight for the United States Championship at Battleground, but the feud has been so good that the two will likely also meet at SummerSlam.

Roman Reigns vs. Bray Wyatt

WWE has done a good job of helping the crowd fall back in love with Reigns after the former Shield member was often booed in the months leading up to WrestleMania 31. He didn’t win the Money in the Bank briefcase, even though he was the heavy favorite, and he could remain out of the WWE World Heavyweight Championship picture for a while. He’ll face Wyatt at Battleground, and while the feud could be done after just one match, that’s not likely for two of WWE's top young stars.

Dean Ambrose vs. Sheamus

Ambrose is just leaving the title picture, and Sheamus holds the Money in the Bank briefcase. They are two of the biggest names in WWE with not much direction for SummerSlam, so a match between the two wrestlers makes sense. They’ve faced each other at recent live events and on “Raw,” so WWE could be preparing to put them in a feud against each other.

Bella Twins vs. Charlotte/Paige

WWE is clearly setting the stage for someone from the NXT women’s division to join the main roster. With the rest of the Divas refusing to help Paige in her quest to take down Nikki and Brie Bella, it looks like someone from NXT will step up. Charlotte and Sasha Banks are the most ready of the NXT women to be called up, but Charlotte no longer has the title and could soon have her first match at a WWE PPV.

The Dudley Boyz vs. Luke Harper/Erick Rowan

An injury that Erick Rowan sustained at a live event might prevent this match from happening, but it could be a highlight of the PPV if he’s healthy. The seeds for the match were planted when the Wyatt Family members reunited and began using The Dudley Boyz’s finisher, calling it “The Way.” Bubba Ray Dudley made an appearance at the Royal Rumble, and was even eliminated by Bray Wyatt, so there’s plenty of reasons to make this match happen.

Ryback vs. Big Show vs. Randy Orton (Intercontinental Championship Match)

Ryback and Big Show are still waiting to have a real title match, since The Miz interfered in their fight at Money in the Bank. Orton isn't involved in the current IC Title picture, but it wouldn’t be a surprise to see him get involved since he remains one of WWE’s most popular babyfaces.

The Prime Time Players vs. The New Day vs. The Lucha Dragons (Tag Team Championship Match)

The New Day are likely to remain in the title picture, even if they don’t hold the belts, since they’ve been the most entertaining tag team since WrestleMania 31. The Prime Time Players are likely to be champs for more than just one PPV, and the inclusion of the Lucha Dragons makes sense, since a lot of tag team matches at big WWE PPV’s include more than two teams.