Last season, when Juan Rivera showed some signs of life, I kept hearing, “Rivera is an RBI machine!” If Rivera was an RBI machine, he was a pretty lousy one, only raking in 47 RBIs the entire season. That’s only one-third of the total RBIs of the 2012 Triple Crown winner, Miguel Cabrera. But the point of this post isn’t to put stock into RBIs, it is to place them in correct context (protip, there is no correct context for RBIs.) The fact that Rivera had 47 RBIs but was considered an RBI machine is ridiculous. Sadly though, Miguel Cabrera’s RBIs are equally meaningless.
A player is granted an RBI whenever a run is scored as a result of that player’s at-bat. An RBI can occur for a number of reasons: A hit, a home run, a walk, and even being hit by a pitch. Again, like with ERA, RBIs seem to make sense. Why shouldn’t we care about Runs Batted In? Isn’t the point of baseball to score more runs than the other team? And if a run is scored, shouldn’t the player be credited for his contribution? The true problem with RBIs doesn’t lie in the answer to these questions. Let’s take a look at both Rivera’s and Cabrera’s stat lines in relation to their RBIs
Rivera had 339 plate appearances, mostly behind offensively weak players. Cabrera had 697 plate appearances behind a stacked Detroit lineup. From the beginning of the season, until the end of June, Rivera managed to hit 24 RBIs. Cabrera had 64 RBIs in that same time span. Interestingly, Cabrera was also being called an RBI machine. For one reason or another, that moniker was considered appropriate for a player whose RBI total was paltry compared to the future 2012 Triple Crown winner. Were Rivera’s RBIs more valuable to a Dodger offense that had gone limp towards the end of May and through June? Perhaps. Consider this, during the middle of the 2012 season the Dodger offense consisted of Tony Gwynn, Jr., Dee Gordon, and Bobby Abreu. There was simply no way Rivera could keep on pace with Cabrera when he had to bat after guys that just could not get on base. Cabrera, on the other hand, was batting behind players like Austin Jackson and Quentin Barry – players who had a .377 and .330 on-base percentage that season.
Another problem for Rivera was the fact that he had almost half the number of plate appearances as Cabrera. If he had the same number of plate appearances, he would have definitely batted in more runs (maybe not, because bad is bad.) However, Rivera still would not have had 139 RBIs, again because he would have still had to have bat behind players that could not get on base. If Rivera was in the lineup behind Austin Jackson and Quentin Barry, would he have had more RBIs? Definitely, but he still wouldn’t have had anywhere near the number of RBIs as Cabrera because Rivera could barely hit (.244 batting average), he could got on base (.286 on-base percentage) because hell, even a blind squirrel finds a nut, and when he did hit, he couldn’t hit for power (.375 slugging percentage.) So what does all of this mean?
Miguel Cabrera’s RBIs are inflated. Detroit put a dude that can hit, and can hit for power, behind two dudes that were really, really good at getting on base. Rivera’s RBIs were not inflated, nor were they deflated. He was batting behind guys that could not get on base to save their lives, and Rivera swung at a ball with a wet noodle.Yet, if Cabrera were hitting behind the likes of Dee Gordon and Tony Gwynn, Jr., he definitely would not have won the Triple Crown. Simply, RBIs are a mix of opportunity and luck, with some skill thrown in.
If you really want to measure the effectiveness of a batter, take a look at their on-base percentage and slugging. Both are simple, yet more elegant, statistics than RBIs. You can easily see that even if both men were RBI machines in 2012, Cabrera was getting on base and crushing the ball more frequently than Juan Rivera.
TL;DR: Cabrera good, Rivera bad.