We have just started the second “half” of the MLB season. The reason for the air quotes is that the definition of half a season in MLB is determined by if a game was played before or after the All-Star Game of that season. The All-Star game doesn’t take place after everyone has played 81 games it takes place somewhere in the second or third week of July and it usually means that some teams have played over 90 games by the end of the first “half”.
This leads to some inconsistencies when you look at performances of halves between seasons but rather than get hung up on an odd definition lets look back on the first half from an analytical point of view.
Overall – The HR Derby
It would be remiss of me to talk about anything else than this first. The HR Derby. No, I am not talking about the classic that happened on the Monday before the All-Star game. I am talking about the rise in home runs during regular season games. So far in 2019, 3.58% of plate appearances end in home run. Which as you have probably heard elsewhere is an all time record for MLB.
There are various articles out there showing that baseball itself is responsible for most of this (this article here from Dr. Meredith Wills in The Athletic is probably the best). So, I won’t go into the details but it simplifies down to the ball in 2019 is smoother and closer to a perfect sphere than before. This means less drag in the air and balls when hit, go further.
So what other effects has this had on 2019 so far?
Highest Isolated Power (ISO) Ever – .180
Highest Home Run Per Fly Ball Rate since records began (2002) – 15.1%
Highest Hard Hit Rate (95+ mph) since records began (2002) – 38.0%
Highest Strikeout Rate Ever – 22.8%
Highest Three True Outcome (K,BB, HR) Rate Ever – 34.9%
What these all say is the ball is more regularly going harder and further than ever before. Because of that we are seeing more runs per game (10.25) than any season since 2007.
Teams – The Good, The Bad & The Ugly
If I asked you which teams have performed and which haven’t, most peoples answers would be similar. I am going to use the FanGraphs projections system to quantify how well teams have performed. The table below show the difference between a teams projected wins at the start of the season and now, as well the difference in playoffs and World Series odds.

It probably isn’t that surprising that the biggest losers are probably the Indians. Their decrease in projected wins along side the increase from the Twins put the Indians at 52.6% playoff odds, down from 97.6%.
If you are inclined to say a team that has a 50% chance of postseason, isn’t really having that bad of a season then you may be inclined to say the Mets have had the worst season so far taking their playoff odds from 39.6% preseason to 5.3% now.
The potential playoff picture on the whole though doesn’t look to different from what was expected. But there is some interesting bits to pick out of the end of season projections.

Projections now have 3 teams reaching the 100 win mark which would match last season. The team that would lose out in the AL Wild Card race would have a better record than the 3rd best NL team. Which would reinforce the images of the American League being the land of the haves and the have nots, whilst the National League is the land of opportunity (to lose to the Dodgers in NLCS).
You may want to feel sorry for the Athletics, Rangers and Angels. They all have severely reduced odds for making the playoffs despite their records as they have to finish above either the Astros or two of the Rays, the Red Sox or the Indians.
On the National League side, the second wild card slot is up for grabs. The first spot looks like it will go to whomever finishes second in the NL East, between the Braves and the Nationals. The second wild card spot however, is up for grabs. Only the Giants and Marlins are more than 5 games away from the Brewers projection of 82.7. Some teams will better their projections but there second wild card spot could be gotten by 85 or less wins.
So, how have teams been achieving the results so far? Let’s look at the runs above average for 2 hitter categories (Offence and Defence) and runs above replacement for the pitching two (Starters and Relievers).

Most of these are not that shocking but seeing the Phillies with a high defensive score when that was an area they were particularly poor at last season.
The Mets spent money and traded prospects to get a good set of relievers this season and it hasn’t worked out so far, Jeurys Familia and Edwin Diaz have combined for and ERA of 6.42 over 64.1 IP.
The Tigers have been poor with the bat and in the field, if it wasn’t for the performances with the ball in hand they would be in a much worse situation. If they were to trade Matthew Boyd or Shane Greene that projection will more than likely dip below 60 and another 100 lose season may be on the cards.
Players – Same old, Same old …… wait what?
The best hitter by fWAR is MIke Trout at 6.1 and the best pitcher is Max Scherzer at 5.5. Nothing unexpected there. Trout is pursued by Cody Bellinger (5.6) and Christian Yelich (5.1), who are currently separated by their defensive contributions. Scherzer is chased by Lance Lynn (4.4). Excuse what, Lance Lynn is the best pitcher in the AL?
Lynn has been very good this season but we, and by that I mean I, shouldn’t have been as surprised by it as we (I) are (am). Something happened last season as Lynn was traded to Yankees at the end of July last season, he changed his pitch mix up and picked up 2 fWAR over just 54 IP as a Yankee. He continued to work on this during the off-season and with this new mix and a change in arm slot, he is almost a new pitcher (read here for more details). Since that trade he has been the best pitcher in the AL, ahead of Gerrit Cole and Shane Bieber who are 0.8 and 1.5 fWAR behind Lynn respectively.
If you look at the top relief pitchers in 2019 by fWAR, only one name stands out as being a real surprise.

You have 7 of the best closers in baseball and Liam Hendriks. As a reliever, Henricks has a 0.92 ERA, a 2.01 FIP and a 4.00 xFIP. Which is quite unique to say the least.
The main reason behind this fairly ludicrous stat line is his HR/FB rate which is at 1.8%. Which is significantly below the record league wide rate we have seen in 2019. He has given up just 1 home run, even though he has allowed a fly ball rate of 50.4% on balls in play. Which is a career high fly ball rate but a career low home run rate. All of this screams red flags of luck for the analytically inclined, so we need to look at his Statcast numbers to see if he is getting lucky or not.

Hendriks has been one of the best xwOBA (Expected Weighted On-Base Average) which means he isn’t getting lucky with fly balls going for outs and not hits/homers. He has been generating popups this season and has been legitimately one of the best relief pitchers this season but hasn’t been used in high leverage occasions so far for the Athletics. It will interesting to see if that changes.
The second half of the season is always ripe for someone and team to flourish unexpectedly, look at Lance Lynn, we don’t know who that will be and if they will ever repeat it. But, to me, that is why this sport is so interesting.