John Cena WWE SummerSlam
John Cena has lost the WWE Championship match at SummerSlam in four straight years. Getty

SummerSlam 2015 is the second-biggest pay-per-view of the year, and WWE is making it nearly as big as WrestleMania. The event has been extended to four hours long, as The Undertaker and Brock Lesnar will headline the card in a highly anticipated rematch.

Even when the PPV is three hours, it highlights some of the biggest moments of the year in WWE. Titles often change hands, including three at last year’s SummerSlam, setting up storylines that can run all the way up until WrestleMania.

Below are five interesting facts about SummerSlam.

John Cena's WWE Championship Failures

The face of WWE has had a few of his shortest title reigns in recent years, but it looks like SummerSlam 2015 will mark the fifth straight year in which Cena will be involved in the WWE title match. But if recent history is any indicator, Cena won’t be victorious when he likely puts up his United States Championship against Seth Rollins’ WWE World Heavyweight Championship.

Cena lost to CM Punk in their 2011 match to determine the undisputed WWE Champion, only to see Alberto Del Rio take the title from Punk minutes later. The following year, Punk kept the WWE title by pinning Big Show in a triple threat match. Cena entered 2013 as the WWE champ, only to lose clean to Daniel Bryan. Last year, Cena lost to Brock Lesnar in one of the most one-sided WWE Championship matches in history.

Brock Lesnar’s SummerSlam Dominance

The Beat Incarnate doesn’t have a perfect SummerSlam record, but he’s been unbeatable at the PPV in his second tour of duty with WWE. Since making his return in 2012, Lesnar has gone 3-0 at SummerSlam in a few memorable matches.

Lesnar and Triple H had a year-long feud from 2012-2013, and their first match saw Paul Heyman’s client force WWE's COO to tap out to the Kimura Lock. The following year, Lesnar beat CM Punk in his last SummerSlam match, winning a no DQ match. Lesnar decimated Cena in the main event of last year’s SummerSlam, and it looks like SummerSlam 2015 will mark the third time in four years that Lesnar’s match will close out the show.

At SummerSlam 2002, Lesnar defeated The Rock a little more than five months after making his debut to become the youngest WWE champ of all time.

The Undertaker Returns To SummerSlam

The Undertaker has performed almost exclusively at WrestleMania in recent years, and he hasn't been on the card for another PPV since 2010. But it’s been even longer since the Deadman fought at SummerSlam.

It’s been seven years since The Undertaker had a match at SummerSlam, defeating Edge in a Hell in a Cell match to end SummerSlam 2008. He wasn’t on the card in 2009, though he did appear at the end of the PPV, delivering a Chokeslam to CM Punk after he beat Jeff Hardy to win the World Heavyweight Championship. The Undertaker had six PPV matches in 2010, but he missed SummerSlam with an injury.

Few Cash-In Attempts

SummerSlam seems like the perfect time for a Money in the Bank cash-in attempt, but it’s not something that’s happened often. Only two times have briefcase winners demanded a WWE Championship at the year’s second-biggest PPV, though both have occurred recently.

The first came in 2011 when Del Rio cashed in his briefcase to take the title from CM Punk. After a Kevin Nash Jackknife Powebomb left Punk lying in the middle of the ring, Del Rio delivered a kick to Punk’s head that won him the title. Two years later, Randy Orton used Triple H’s help to cash in his Money in the Bank contract and beat Daniel Bryan for the title, starting a feud that lasted until WrestleMania 30.

Rematches

Because there are so many PPVs, it’s hard to find many matches on a card that have never happened before. But some of the biggest matches at SummerSlam 2015 stand out as rematches.

The Undertaker is looking to get revenge on Lesnar after his WrestleMania streak was broken a year and a half ago. Rollins and Cena have never fought with multiple titles on the line, but their tables match at TLC 2014 set up their triple threat match at the Royal Rumble for the WWE World Heavyweight Championship. Rollins and Erick Rowan won’t be involved when Roman Reigns and Dean Ambrose face Bray Wyatt and Luke Harper, but The Shield and The Wyatt Family faced off at Elimination Chamber in one of the best matches of 2014.

It’s looking like Randy Orton and Sheamus will have a rematch of their match from Battleground in July. Dolph Ziggler has never faced Rusev at a PPV, but he might team up with Lana against Rusev and Summer Rae at SummerSlam. Ziggler was involved in a mixed tag match at SummerSlam just two years ago.