Later this month -- Jan. 22, to be precise -- longtime New York Yankees closer Mariano Rivera will be announced as one of the newest members of the National Baseball Hall of Fame. He has appeared on every public ballot thus far according to Ryan Thibodaux's indispensable tracker, and it is a safe bet Rivera will receive the 75 percent needed for induction.

Here, for reference, are the highest Hall of Fame voting percentages in history:

  1. Ken Griffey Jr.: 99.32 percent
  2. Tom Seaver: 98.84 percent
  3. Nolan Ryan: 98.79 percent
  4. Cal Ripken Jr.: 98.53 percent
  5. Ty Cobb: 98.23 percent
  6. George Brett: 98.19 percent

No other players appeared on at least 98 percent of submitted Hall of Fame ballots. Not Hank Aaron (97.83 percent), not Babe Ruth (95.13 percent), not Willie Mays (94.68 percent), not Ted Williams (93.38 percent). Chances are Rivera will not be the first unanimous Hall of Famer in history. He does have a shot at a record voting percentage, however.

In parts of 19 big league seasons Rivera used his trademark cutter and pristine command to finish with a record 652 saves and post a 2.21 ERA in 1,283 2/3 innings. For comparison's sake, Hall of Fame closer Trevor Hoffman allowed 38 more runs than Rivera in 194 1/3 fewer innings. Hoffman was Rivera's contemporary but he was not his equal. No one was. Rivera stands alone as the greatest reliever in baseball history.

So, with the Hall of Fame announcement a week away, let's go back in time to relive Rivera's greatness and put his career into context. Come with me, won't you?

Rivera was a failed starting pitcher

Yep. Rivera came up through the minor leagues as a starting pitcher and he made his MLB debut as a starter with the Yankees in 1995. He went 3-3 with a 5.94 ERA in 10 games and 50 innings as a starter for the Yankees that season. They were the only 10 big league starts of his career.

On Independence Day 1995, Rivera threw the best start of his career, striking out 11 and allowing two hits in eight shutout innings against the White Sox. To the action footage:

Back then pitchers were ashamed to move to the bullpen. It was almost an insult that they weren't good enough to start. That isn't so much the case nowadays. Bullpens are a huge part of the game, so much so that pitchers are groomed to be relievers in the minors. Rivera probably didn't like being moved into a relief role in 1995. It turned out to be one of the best decisions in baseball history.

He had his best season before he became a closer and before he had the cutter

Rivera is the greatest closer in baseball history, and, in one season, he was arguably the greatest setup man the game has ever seen. In 1996, Rivera threw 107 2/3 innings with a 2.09 ERA and 130 strikeouts as John Wetteland's setup man. Rivera threw those 107 2/3 innings in only 61 appearances. He often pitched the seventh and eighth innings.

Here, by WAR, and the five greatest seasons of Rivera's career:

  1. 1996: 5.0 WAR
  2. 2008: 4.3 WAR
  3. 2004: 4.2 WAR
  4. 2005: 4.0 WAR
  5. 2006: 3.9 WAR

The season as a setup man was Rivera's best, not one of his seasons as closer. And, because that's not crazy enough, Rivera had not even learned his cutter yet. As Scott Miller wrote in 2013, Rivera learned his cutter in 1997. He was playing catch with teammate Ramiro Mendoza one day and the ball just started the cut, and that was that. The cutter had arrived. Rivera's best season came without his cutter and before he became a closer. Pretty incredible.

He struggled in his early days as a closer

The Yankees let Wetteland leave as a free agent following his World Series MVP performance in 1996. Then they plugged Rivera into the ninth inning. It didn't go so well at first. Rivera blew three of his first six save chances. Here's what Jack Curry, then of the New York Times, wrote on April 17, 1997:

Mariano Rivera, we have seen John Wetteland. You are not John Wetteland. Not yet. Maybe never. That's not a serious criticism. Wetteland's 179 saves over the last five years are second in the major leagues to Randy Myers's 181.

So far this season, Wetteland has four saves in four opportunities for Texas and has not allowed an earned run in six innings. Rivera has three botched saves in six opportunities. As difficult as this is for the new closer to digest, it might be the best thing that has happened to the Yankees through the first 14 games. Sound strange? The Yankees have now seen in living color that this is definitely a new season. They should be thankful for the early warning. Better to get shocked in April than in August.

Hard to believe that was once written about Rivera, isn't it? From that day forward, Rivera pitched to a 1.58 ERA in 62 2/3 innings and saved 40 games in 46 chances. He held opposing batters to a .217/.275/.315 batting line. Rivera saved more games than anyone in history yet even he struggled initially after moving into his new role.

Rivera is the greatest run-preventer in history

MLB: ALDS-Cleveland Indians at New York Yankees
Mariano Rivera is a week away from being announced as a Hall of Famer. USATSI

On a rate basis, no pitcher in baseball history was better at preventing runs than Rivera. It is not even close. Over 1,200 pitchers have thrown at least 1,000 innings in the big leagues. Here is the top of the ERA+ leaderboard:

  1. Mariano Rivera: 205 ERA+
  2. Clayton Kershaw: 159 ERA+
  3. Pedro Martinez: 154 ERA+
  4. Joe Devlin: 150 ERA+
  5. Lefty Grove: 148 ERA+

ERA+ is park and league adjusted, so it can be compared across eras. In a nutshell, Rivera's career 205 ERA+ means he was 105 percent better than preventing runs than the league average pitcher. No one else is close. Does Rivera have an unfair advantage as a reliever? Sure, it's possible, but the next best mark by a reliever is a 147 ERA+ by Hall of Famer Hoyt Wilhelm.

Just to further put this into perspective, the gap in ERA+ between No. 1 (Rivera at 205) and No. 2 (Kershaw at 159) is equal to the gap between No. 2 (Kershaw at 159) and No. 250 (several tied at 113).

His postseason performance is unmatched

A case can be made Rivera is the greatest postseason performer in baseball history. Maybe in sports history. The Yankees were in the postseason pretty much every season during his career, leading to Rivera throwing 141 innings in October. That is equivalent to two extra seasons. In those 141 innings Rivera allowed ...

  • ... 11 earned runs (0.70 ERA) and two unearned runs.
  • ... 86 hits and 21 walks (0.76 WHIP).
  • ... two home runs (0.13 HR/9).

Rivera of course had some notable postseason failures (like this, this, and this), but, by and large, he was an unmatched force in October. He pitched in 32 different postseason series and allowed multiple earned runs in exactly one of them, the 2000 World Series against the Mets. Also, he went multiple innings in 31 of his 42 postseason saves -- 31 of 42! -- so he often served as his own setup man. 

Check out the career postseason win probability added leaderboard. Win probability tells us how much a player contributed to his team winning an individual. Add it all up and you get the player's career total. Rivera is first by a mile:

  1. Mariano Rivera: 11.7
  2. Curt Schilling: 4.1
  3. John Smoltz: 3.6
  4. Andy Pettitte: 3.5
  5. Jon Lester & David Ortiz: 3.2 (tie)

All those high-leverage innings add up to, by far, the highest career postseason win probability added in baseball history. Rivera's total is higher than Schilling's, Smoltz's, and Petitte's combined. Having so many opportunities to pitch in the postseason certainly helps, but that's also kind of point, right? Rivera answered the bell again and again.

Against the best competition and in the most pressure-packed games of the year, Rivera was a workhorse and overwhelmingly dominant. He didn't just carry his regular season performance over into the postseason. He took his game to another level, a level that puts Rivera among the greatest postseason performers ever.

Rivera was great at avoiding losses

Edwin Diaz was arguably the best closer in baseball last season. He saved 57 games and pitched to a 1.96 ERA with 124 strikeouts in 73 1/3 innings. An incredible season. And do you know what Diaz's record was? 0-4. Zero wins, four losses.

That's not intended to be a knock on Diaz. It's intended to show how hard it can be for closers to get wins. When they enter the game, their team usually already has the lead. A closer typically gets a win one of two ways. Either he enters into a tie game and his team takes the lead, or he blows the save and his team retakes the lead. That's about it.

That's what makes Rivera's career 82-60 record (79-57 as a reliever) so impressive. It's not so much that he racked up wins. It's that he avoided losses. Consider the win-loss record of the top five relievers on baseball's all-time saves list:

  1. Mariano Rivera (652 saves): 82-60
  2. Trevor Hoffman (601 saves): 61-75
  3. Lee Smith (478 saves): 71-92
  4. Francisco Rodriguez (437 saves): 52-53
  5. John Franco (424 saves): 90-87

Rivera is 22 games over .500. The other four are a combined 33 games under .500. Again, that's normal! You'd expect a closer to have more losses than wins. That's the nature of the job. Rivera is the exception. He got wins like everyone else, but he was great at avoiding losses. Far better than other top closers in history.

By any measure, Rivera is the greatest reliever in baseball history. He has the most saves. He has the best ERA+. He leads all relievers in WAR (by a lot). His postseason track record is close to impeccable. Rivera's Hall of Fame case is as flawless as it gets and it shows in his voting percentage. He might not go into the Hall of Fame unanimously, but Rivera should challenge Griffey's all-time voting percentage record, and it wouldn't be undeserved.