Who Will Be Baseball's Next Mariano Rivera?

The conclusion of the 2013 MLB season will represent the end of an era, as legendary Yankees closer Mariano Rivera is set to call it a career after a fantastic 19-year run that will see him go down as the greatest reliever in baseball history.

There may never be another pitcher quite like Rivera, who has been so dominant for so long and essentially relied on one pitch, a cut-fastball, to do it. Nonetheless, his retirement begs the question, who could be the next Mariano Rivera?

First let's take a quick look at Rivera's career, for comparison's sake, and see what anyone trying to follow in his footsteps is up against.

Rivera broke into the league in 1995 at the age of 25, and after pitching in 19 games as a rookie, he spent the 1996 season setting up for one of the best in the business in John Wetteland while helping the Yankees secure a World Series title.

Wetteland departed in free agency after that season, and a 27-year-old Mariano Rivera saved 43 games with a 1.88 ERA in his first season in the ninth-inning role.

That would be his first of nine 40-plus save seasons, which has him tied with Trevor Hoffman for the most all-time. In fact, Rivera has saved at least 30 games in every season since becoming closer except for 2002 and 2012, the only two years during which he missed significant time due to injury.

Rivera's legacy goes far beyond his record 651 (and counting) regular-season saves, though, and it has been his postseason dominance that has really set him apart and made him not just the best closer of all time, but one of the greatest pitchers in baseball history, period.

In 96 postseason appearances, Rivera has converted 42 of 47 save chances to go along with a 0.70 ERA and 0.76 WHIP. He has a pair of ALCS MVP awards and the 1999 World Series MVP award to his credit, and in total, he has won seven AL pennants and five World Series titles.

It's a resume that will make him a first-ballot Hall of Famer, and is good enough for some to say there may never be another pitcher nearly as dominant for as long as Rivera was. For a pitcher to even come close to Rivera, he not only needs to have sustained success in the ninth-inning role and avoid injury, but he also needs to be in a position to make perennial trips to the postseason. With that in mind, here are the three guys who appear best positioned to be baseball's next Mariano Rivera.

RHP Carter Capps, Seattle Mariners

This is my dark-horse pick, as it relies on Capps getting on track after a less-than-stellar rookie season and the Mariners making a run at the type of sustained success that their talented young core suggests they can.

Capps, a third-round pick out of Mount Olive College in 2011, wasted little time reaching the big leagues. He posted a 1.23 ERA and a 13.1 K/9 mark with 19 saves in the minors last season before earning a call-up to Seattle.

After a solid late-season showing, he broke camp with the team this season, and despite a 5.37 ERA, he has been one of the Mariners' more often-used relievers this season.

If you remove a rough patch in the middle of the season in which he allowed a run in six straight appearances, his ERA is a much more respectable 3.43 over his other 41 appearances.

His 10.2 K/9 mark shows the dominant stuff he possesses, highlighted by a fastball that reaches triple-digits and a good slider/changeup combination. Unlike many young, hard-throwing relievers, command is not his issue; he just needs to do a better job missing bats.

Still just 23 and likely to be closing games in Seattle sooner rather than later, even with Danny Farquhar pitching well in the role this season, Capps could quickly ascend to the ranks of the game's elite closers and stay there for a while.

RHP Kenley Jansen, Los Angeles Dodgers

As far as a pitcher matching up to Rivera from a repertoire sense, Kenley Jansen is hands down the closest comparison, as he too relies on a dominant cut-fastball more times than not.

According to FanGraphs, Jansen has thrown the cutter 86.5 percent of the time this season, mixing in the occasional four-seam fastball and slider, but essentially relying on that one dominant pitch.

Also like Rivera, Jansen had a dominant 25-game stint his first year in the league and then served as a dominant setup man in his first full season with the Dodgers. However, he still does not have a full season in the closer's role under his belt.

Last year, he led the Dodgers with 25 saves and put up dominant numbers across the board, with a 2.35 ERA and 13.7 K/9, but an irregular heartbeat led to him being shut down late in the season.

That was reason enough for L.A. to re-sign Brandon League to a three-year, $22.5 million deal and enter the season with him as the closer, but when he struggled early, Jansen again took over ninth-inning duties and has thrived once again.

In 69 appearances on the season, he's 25-of-28 on save chances with a 1.91 ERA and 102 strikeouts in 70.2 innings of work. As long as health issues don't crop back up, he should be the unquestioned closer next season, and the 25-year-old will also have a chance to prove himself in October this year.

RHP Craig Kimbrel, Atlanta Braves

The most likely candidate to put together a Rivera-esque career at this point looks to be Braves flame-thrower Craig Kimbrel.

After a dominant performance as setup man down the stretch in 2010, in which he allowed just one earned run and struck out 40 in 20.2 innings of work while bridging the gap to Billy Wagner in the ninth inning, Kimbrel took over as closer in 2011.

He saved 46 games with a 14.8 K/9 mark and 2.10 ERA, winning NL Rookie of the Year honors and announcing himself as one of the game's most dominant young arms.

That was followed by 42 saves and a 16.7 K/9 mark with 1.01 ERA last season, and so far this year, he has has 46 saves and a 13.1 K/9 mark with a 0.91 ERA.

There is little debate that the 25-year-old Kimbrel is the most dominant reliever in the game today, and seeing as he got a three-year head start on Rivera in assuming the closer's role, he could make a legitimate run at his all-time saves mark as long as he stays healthy.

However, he has a long way to go in proving himself in high-pressure situations and in the postseason. He's remembered as much right now for his dominant regular-season numbers as he is for blowing the save that kept the Braves out of the postseason on the final day of the year back in 2011.

He'll get a chance to prove himself this year with the Braves eyeing a lengthy postseason run, and looking to the future, he seems to be in as good a position as anyone to regularly find himself pitching in October.