Your 2017 Giants: Mac Attack!

Interesting The Hardball Times study on metrics related to MLB flyball length, and therefore, homerun power.  He looked for predictive signals within batted ball data and hope to uncover a couple of otherwise unknown potential power hitters. The data was sourced from the MiLB pitch-by-pitch gameday files and are subject to recording bias and human error. He did not attempt to clean the data (probably a huge job, and this was a first effort at looking at what the data said; if the data analysis ends up being predictive, future efforts undoubtedly will look to clean the data as well).

It ended with a projection table of AA and AAA hitters who has not had extensive experience in the majors yet, and Mac Williamson was 21st on the list.  His MLB projection was nearly 300 feet, based on his MiLB pitch-by-pitch stats.  He was nearly 18 feet behind the leader, but a much closer eleven and a half feet behind the second player, and only four feet away from a top ten placing.  There was no indication of what the standard deviation was, but four feet out of 300 seems like it would be within range of error.

However, he was one of the oldest players on the list, one of three (out of 26) born in 1990, and power comes with age, so if adjustments were made by age, he would fall further down the list relative to his younger colleagues on the list.  Still, he made a list of possible upper minor's power hitters.
ogc thoughts

Mac Williamson has been an interesting pick from the time the Giants selected him third in the 2012 draft.   Considered a poor man's alternative to Richie Shaffer, a first rounder of the Rays that draft, the Giants picked him up in the third round with the 115th pick, even though Baseball America (236 out of 500, putting him more in the mid-to-late 7th round talent) had him much lower on their list.   In spite of this divergence, the Giants tried to get him to sign to a much lower bonus, in order to free up bonus to spend on a high schooler that they had drafted in the 30's (that's the way their draft has evolved in recent years, the 30's are fliers they take mostly on high schoolers who fell due to signability issues, like John Riley, one of the few big signs that they have done so far, that far back in the draft, with this strategy), but he held out for just short of the slotted amount (which ended up being paid almost exactly to another draft pick signed at the same time, Martin Agosta, who has so far fizzled out as a prospect, but there is still hope that perhaps he could be a reliever).

Mac has hit well most of the way up the farm system, starting to come back down to regular hitting in AA and AAA, but even there, he has hit around .800 or better, even though he has mostly been on the younger side for the league (but never young for the league until he reached AAA and the majors, when he was around 3-4 years younger).  He has handled AAA OK, so it was not a surprise that his first try in the majors wasn't that great.

And in the majors, he has actually been OK.  While he has not hit well for average, he was able to get a lot of walks as well as hit for power, resulting in OK batting line of .223/.315/.411/.726, with a very good ISO of 188.  His main problem is striking out so much, but he's actually OK if he's the 7th batter in the lineup, where in the NL, the average 7th place hitter hit .248/.315/.388/.705.  So, in spite of all the complaints about his hitting, and the demand for a good free agent LF, Williamson, if he can continue to hit like he did in 2016, but over a full season, would be an above average contributor to the Giants lineup.

On top of that, per Baseball-Reference.com, he added 0.2 dWAR last season. His Rtot/YR was 27 and Rdrs was 45 (anything over 0 is above average, anything above 0.5, I would say is good, at 10, that means you are adding one win per season, and the best seasons are in the 20-30 range generally).  So there is some possibility that he'll be good defensively, though small samples tend to be be wildly erratic (he was negative in 2015, for example).  But he has had a good rep for defense that I can remember, with an especially strong arm, plus good speed, that should result in good comparisons for him defensively in LF, as that is the position that teams normally put weak arms and slower players.

The only hitch is that Jarrett Parker has also been hitting well too, even better (but he is older, so that is an advantage for him).  He's also got an arm, plus speed, and could play CF in a pinch even better than Williamson.  So while it would be better for Williamson to get all the ABs he can get, the team will probably prefer to play whoever is playing better.

Should be an interesting season for one or both players in 2017, I feel good that at least one of them will do well.  Plus, there is Gorkys Hernandez, who could also play LF if necessary, he's probably going to be the backup CF, he did well for the Giants last season.