What Eric Thames is doing right now is fucking nuts. Through just 12 games entering Tuesday night he is batting .405 while leading the league in home runs (7), runs scored, slugging, OPS, OPS+, and total bases. You may remember him from his first stint in Major League Baseball with the Blue Jays and Mariners in 2011/2012. In those two seasons Thames was a free swinger who compiled 175 strikeouts compared to just 38 walks. He had power, no doubt, but that type of strikeout to walk ratio is practically impossible to sustain for a big league hitter.
Following a 2013 season spent in the minors Thames asked for his release and then went to play in Korea for three years. In this USA Today article he credits the Korean league for teaching him plate discipline as well as teaching him the mental side of baseball. It's a cool story of the transformation from a major league castoff to becoming a Korean superstar that earned him the nickname "God". In three seasons in Korea Thames batted .348 with 124 home runs. In 2015 he hit 47 long balls while stealing 40 bases and won league MVP honors. But most importantly he began walking at much a higher rate while striking out at a much lower one.
We have just two weeks of data to go off of, but so far there are two advanced metrics that really highlight how good Thames has been. The first one is isolated power (ISO). You can read more about it here but what you need to know is ISO measures how many extra bases a player averages per at bat. Basically, it tells you whether or not a player is a legit power hitter. Typically a good ISO is anything above .200. In 2016 David Ortiz led baseball with a .305 ISO. For more historical perspectives Babe Ruth had a .473 ISO in 1920 and Barry Bonds had a .536 ISO in his 73 homer 2001 season. Entering Tuesday night Thames has an ISO of .595.
That number will regress. Unless we are witnessing the craziest baseball story of all time then Thames is not a Hall of Fame player, or even an MVP caliber one. Instead the reason I point out this stat is to show how dominant his first 48 plate appearances of the season have been. Pitchers will adjust to him and that ISO will come very much back down to Earth. It will then be up to Thames to adjust back to how guys pitch him. But there's another stat that shows his success so far is much more than just a fluke.
This stat is even more nerdy and FanGraphs has a full breakdown of ithere but it is called Z-Contact% and it measures how often a batter makes contact on pitches he swings at in the strike zone. Cruising the leaderboards of this stat you'll find a lot of line drive type hitters with good bat on ball skills such as Mookie Betts and Joey Votto. Think the opposite of what Chris Davis of the Orioles is. What you don't see on that leaderboards list are players with a .595 ISO (okay fine that ISO won't last but the point is you don't see big time power hitters on this list).
Entering Tuesday night's game Thames ranked 28th on the Z-Contact% leaderboard, which signals a massive improvement in strike zone judgement and contact skills from his first stint as a big leaguer. Basically when he swings at a pitch in the strike zone he's making contact. And when he makes contact he's going for extra bases. That's what happens when you combine his Z-Contact% with his isolated power. And remember that ridiculous strikeout to walk ratio he had back in 2011 and 2012? Well so far in 2017 he has struck out 11 times and has taken five free passes. It's not elite, but it's pretty damn good.
If Thames was just hitting for power or only showing improved contact skills, then his contract would still be a success for the Brewers. He is owed $4 million this season, $5 million in 2018, and $6 million in 2019. He also has a $7.5 million player option in 2020 that at this rate he won't be picking up. Thames is 30 years old right now, which means he will be entering his age 33 season at the earliest when he reaches free agency. That's a long ways away so he may never be properly compensated for how well he's playing right now. Then again it's only April 18th. Like I mentioned earlier pitchers are going to adjust to him. What is going to separate him from being a flash in the pan to a star in this league is whether or not he adjusts back. His newfound contact skills give him such a high floor that I'm betting he'll do just fine.