Rock Mining week 18: Development of young Rockies bats in 2013

A quote at the bottom of ESPN's game wrap last night intrigued me, "Since mid-June, Rosario is batting .328 with 11 doubles, a triple, 6 home runs and 24 RBIs in 38 games." I knew Wilin had been doing better of late, but I had not quite realized it was that much better. With the focus here at the Row lately on getting better players to surround our stars, this week I decided to look at how the young players have developed over the season. Specifically, I will look at two second year players in Wilin Rosario and DJ LeMahieu while also looking at rookie call-up Nolan Arenado.

Wilin Rosario

Rosario had a huge rookie year, at least offensively. Breaking Todd Helton's record for rookie home runs by hitting 28 was no small feat and I had concern about a sophomore slump. It took a month of April where he hit .350 with seven home runs, but pitchers finally stopped throwing him fastballs and his offense went into a tailspin in May until the middle of June. One of the biggest changes in his approach is that he appears to be swinging more for contact now than home runs.

As proof to this, Rosario's line drive rate has raised slightly but there is more than a 10% increase in his ground ball rate with a corresponding decrease in his fly ball rate over the last three months. This has not hurt his overall home run chances though. This is because even though he is hitting fly balls only 22% of the time in July/August vs. 40% of the time in May/June, three times as many of his fly balls are now home runs. This appears to be a change where he is being selective and hitting pitches where they are pitched instead of trying to turn everything into a home run.

As for defense, while I don't think he will win a gold glove any time soon, Rosario's defense has seen significant improvement over last year. In 117 games last year, Fangraphs fielding score gave him -12.2 runs above average. Through 94 games this year, that same metric is down to -5.3 runs. Again, this won't win him awards, but it means that as a player he has already provided the Rockies with 1.3 WAR this year even without as strong of offensive number and in 23 less games.

DJ LeMahieu

DJLM has been serviceable this year only in the fact that he hasn't been as bad as Rutledge turned out to be this year. When he was called up in May, he started with a strong bat, hitting .295 for the month which proved to be his best offensive month, although still below average with a wRC+ of 95. His offensive number have steadily gone down from there with a wRC+ of 78 in June and then 44 in July. August is looking slight better for him so far, but still a small sample size.

With other lineup anchors like Pacheco no longer here, it is ok to have someone like D. J. in the lineup because of his glove. His fielding in 73 games has been worth 5.1 runs above average according to Fangraphs. This is far better than the 3.0 he put up for the team last year in 81 games. Fielding stats can be fickle and not necessarily accurate, but because of his defense, DJLM is a net plus for the team, with 0.5 WAR.

Nolan Arenado

Getting what he, and most fans wished for, Nolan is refining his craft in Colorado ever since his call up at the end of April. After having an up and down first half which saw him struggle but also have some clutch hits/home runs, Nolan is having a much better second half of the season. Hitting just .244/.283/.395 before the break, he has increased that to .319/.351/.435 in his 75 at bats in the second half (standard small sample size warning). This has given him an above average wRC+ of 101 for the second half vs. 72 for the first half.

Nolan seems to do better with the more playing time he has. After spending a full month with the team early in the season, his bast got noticeably better at the end of May and throughout June (wRC+ 119). After taking a week off for the All Star Game though, he struggle again coming back before finding his groove again at the end of July. A continued strong showing by him for the next month and a half will give him a strong base heading into next year.

As to defense, he is like DJLM in the fact that he can have an off day at the plate because he brings a great glove to third base. His UZR rating of 16.6 is triple that of anyone on the team not name Tulo or Cargo and it is more than double their ratings of 6.2 and 5.9 respectively. You have to go to Baltimore and watch Manny Machado to find a better fielder at third according to UZR (19.8), and most of that is due to him playing a month more than Nolan as their UZR/150 are very close, Manny's 27.0 vs. 26.1 for Nolan.

Conclusion

Of the three players, DJLM's future with the team is most in doubt. He is the oldest (25, vs. Wilin-24, Nolan-22) and is the most limited offensively. While he brings a good glove, he plays at a position where there are a ton of glove men. He has time to become a better batter, but I seem him most likely filling a Johnny Herrera type of a role on this team if he stays. There are just too many other young middle infielders coming up in the organization with better bats.

Rosario's bat give the Rockies a huge comparative advantage at catcher, similar to Tulo at shortstop. However, this only works if he can become a serviceable catcher. Otherwise, he will likely be moved to first base if/when one of the triumvirate of Murphy/Casteel/Swanner make it to the big leagues. At first base, his bat is still good, but it does not give the Rockies near the advantage of his current position. The team needs to work with Wilin as much as they can and keep the defensive improvement coming. His improvement over the last two months at the plate shows that his is not just a one trick pony and should stay with the team for as long as they can afford him.

Arenado is full of promise and has already proven himself to be the team's best option at third. The Rockies need to keep him busy this winter hitting baseballs so that he gets the volume of experience he needs to be their next young superstar. I hope to have a decade of watching him and Tulo eliminate all opposing hits to the left side of our infield.

This week's Good, Bad, and Ugly

The Good

Home cooking! After only scoring ten runs in two series on the road, the Rockies equaled that number in just three innings of work at home. Whatever Walt said to them, he needs to bottle that up and keep for future use. Additional praise is sent Corey Dickerson's way as he one of the few bright spots offensively on the road this week. In Pittsburgh and New York he hit .353/.353/.529 while batting in a different spot in the lineup almost every day. Only thing that kept him from being the top story this week was not getting a hit of an infielder pitching to him last night.

The Bad

Tyler Chatwood going on the DL put a scare in a lot of us. I do not have further information on the swelling in his elbow, but hopefully the Rockies caught this in time and he will be able to pitch next year and will have a healthy rest of his career. Since he had TJ surgery in high school already, further serious injury could be a bad omen for the future. JDLR getting hit on his throwing arm last night also made my heart skip a beat, although he seemed ok afterwards.

The Ugly

The team's play in New York seemed to lack spirit. I joked earlier about Walt Weiss's talk with the club yesterday before the game, but it was sorely needed. I like watching this team play hard, whether win or lose, but those three games made me find other things to do around the house. If I am doing household chores instead of watching baseball, it must be some ugly baseball.