John Jaso Compared to NL Central First Baseman: Chris Carter

John Jaso has played well as the Pittsburgh Pirates starting first baseman, but how has he compared to the other National League first baseman? First, a look at Milwaukee Brewers first baseman Chris Carter.

The Pittsburgh Pirates non tendered 2015 starting first baseman Pedro Alvarez on December 2, 2015. The club signed current first base John Jaso on December 23, 2015. The Pirates and Chris Carter seemed liked a potential match, as Carter was a potential low cost first base option until Josh Bell made his anticipated debut.

However, the Pirates decided to go with John Jaso over Chris Carter. So far this season John Jaso has been a great addition to the Pirates. But has he been better than Carter? Read on to find out.

John Jaso v Chris Carter

John Jaso has hit .285/.358/.406 with a .764 OPS, meanwhile Chris Carter has hit .230/.299/.519 with an .818 OPS. Jaso has 20 RBIs compared to the 43 Chris Carter has for the Milwaukee Brewers. On the surface, it seems Carter has had the better year. However, RBIs are more of a product of situation – Jaso has had 52 plate appearances with runners in scoring position and Carter has had 63, Carter should have more RBIs- and OPS is skewed heavily by power hitters. Jaso gets on base more and hits for a higher average, so who really is better?

To start, lets take a true value of each players contribution to runs created, using OBP and SLG, the two numbers that make up OPS. To make an accurate assessment, OBP has to be multiplied by 1.8 because in terms of run scoring, OBP is 1.8 times more valuable than slugging. To see which player has been more valuable to run scoring this season – only using these two variables instead of OPS – the formula becomes (1.8(Jaso OBP-Carter OBP))+(Jaso SLG-Carter SLG), and if the value is positive, Jaso’s OBP skills are more valuable than Carter’s ability to hit the ball out of the park, and if the value is negative, the opposite is true.

(1.8(0.358-0.299))+(0.406-0.519)
0.1062+(-0.113)
-0.0068

Carter comes out ahead in both OPS and when you adjust the numbers for the true contribution that OBP makes to run scoring. But there are far more variables in baseball than just how a player gets on base and how much power a player has. It’s also important to look at when a player’s valuable moments have occurred to help them win. It’s also important to look at defense and other advanced numbers.

Jun 3, 2016; Pittsburgh, PA, USA; Pittsburgh Pirates first baseman John Jaso (28) reacts in the field against the Los Angeles Angels during the first inning at PNC Park. Mandatory Credit: Charles LeClaire-USA TODAY Sports /

Run Expectancy, or RE24, is described by Fangraphs as:

"On the hitting side, RE24 is a measure of how well hitters are capitalizing on their opportunities while also not assigning extra credit (like RBI) to hitters who happen to come to the plate with men on base very often."

It’s important to note, that RE24 is not based off of the context of the score or the inning. Jaso comes in with a RE24 of 9.98 and Chris Carter has come in with an RE24 of 0.14. Jaso has been capitalizing on his chances more so than Carter has been.

A more simple approach could be to look at their runners in scoring position splits. Jaso is hitting .286/.392/.452 and a 0.85 with RISP compared to the .149/.241/.343 with a 0.584 OPS with RISP of Carter. Jaso aslo comes ahead (+0.3808) when adjusting the OBP to 1.8 and subtracting the differences in OBP and SLG for their run scoring values.

Another way to look at the players is through their wOBA and wRC+ values. Fangraphs describes wOBA as:

"Weighted On-Base Average combines all the different aspects of hitting into one metric, weighting each of them in proportion to their actual run value. While batting average, on-base percentage, and slugging percentage fall short in accuracy and scope, wOBA measures and captures offensive value more accurately and comprehensively."

The wOBA formula for the current 2016 season is:

wOBA = (0.689×uBB + 0.720×HBP + 0.879×1B + 1.247×2B + 1.578×3B +
2.033×HR) / (AB + BB – IBB + SF + HBP)

Jaso has a wOBA of .335 and Carter 0.342. Carter has the edge here, but both have been pretty average when it comes to their wOBA. Where as Carter has the advantage in wOBA, Jaso has the advantage in wRC+, where Fangraphs gives their description:

"Weighted Runs Created (wRC) is an improved version of Bill James’ Runs Created (RC) statistic, which attempted to quantify a player’s total offensive value and measure it by runs. In Runs Created, instead of looking at a player’s line and listing out all the details (e.g. 23 2B, 15 HR, 55 BB, 110 K, 19 SB, 5 CS), the information is synthesized into one metric in order to say, “Player X was worth 24 runs to his team last year.” While the idea was sound, James’ formula has since been superseded by Tom Tango’s wRC , which is based on Weighted On-Base Average (wOBA)Similar to OPS+, Weighted Runs Created Plus (wRC+) measures how a player’s wRC compares with league average after controlling for park effects. League average for position players is 100, and every point above 100 is a percentage point above league average."

Jaso has a wRC+ of 113, meaning he has a wRC 13 percent higher than the league average. Carter has a wRC+ of 110, Jaso’s been three percent better in creating runs, despite having a lower wOBA.

In fact, the similarities of Jaso and Carter’s wOBA, wRC+, and when comparing their on-base to slugging and adjusting to see who has been higher in terms of run scoring, the two players have been worth the same offensively. Jaso has gone about it in getting on base where as Carter has gone about it by hitting the baseball out of the ballpark.

More from Rum Bunter

Jaso and Carter even have an equal WAR of 0.5 this season, as both have been worth half a win more than a replacement level player. With the glove, these two both have -1 defensive runs saved, and in the terms of traditional defensive numbers, Jaso’s .993 fielding percentage and Carter’s 0.992 fielding percentage are almost identical. There are very little differences in these two players worth, both in producing runs and saving runs.

Jaso has a 3 UZR/150 compared to the -1.9 UZR/150 that Carter has produced, but that isn’t enough to take one player over the other. All across the board they’ve been fairly equal, except in the win probability each has added. Win Probability Added (WPA) captures the differences in terms of value of situation, such as a blowout home run compared to a homerun to give the team a one run lead, and Fangraphs describes it as such:

"Win Probability Added (WPA) captures the change in Win Expectancy from one plate appearance to the next and credits or debits the player based on how much their action increased their team’s odds of winning. Most sabermetric statistics are context neutral — they do not consider the situation of a particular event or how some plays are more crucial to a win than others. While wOBA rates all home runs as equal, we know intuitively that a home run in the third inning of a blowout is less important to that win than a home run in the bottom of the ninth inning of a close game. WPA captures this difference."

John Jaso has managed to have a WPA of 1.18 and Carter a WPA of -0.25. Carter has been less than helpful to his teams of winning when given the opportunities. The amount of opportunities is the problem though. To have higher WPA numbers, you have to be presented with more opportunities, it’s another example of product of situations. When taking each player’s WPA and dividing it by the league index (WPA/LI), we are able to compare the players. Carter once again comes out on top at 0.73 compared to Jaso’s 0.63, but the difference is still small.

In conclusion, both John Jaso and Chris Carter have been very similar players this season. Jaso goes about it in the more sabermetric approach by not striking out and getting on base. Carter goes about it in more of the old school, hit the ball out of the ball park to score runs way. Both have saved -1 runs defensively and have basically the same fielding percentage. In this National League Central battle of first baseman, it really is not clear-cut who is having the better season between Jaso and Carter.

Monday I’ll take a look at Jaso’s 2016 to Cincinnati Reds first baseman Joey Votto’s 2016 season.

*Numbers as of games before Saturday and from FanGraphs

Home/Pirates News