Why did Bryce Harper bat sixth?

Using wOBA from 2013, here is the ranking of the Washington Nationals' hitters in the lineup manager Matt Williams used on Wednesday:

1. Jayson Werth (R)

2. Bryce Harper (L)

3. Ryan Zimmerman (R)

4. Ian Desmond (R)

5. Adam LaRoche (L)

6. Anthony Rendon (R)

7. Jose Lobaton (S)

8. Denard Span (L)

OK, 2013 is ancient history. Here are those players ranked by 2014 projected wOBA from ZiPS:

1. Bryce Harper (L)

2. Jayson Werth (R)

3. Ryan Zimmerman (R)

4. Anthony Rendon (R)

5. Ian Desmond (R)

6. Adam LaRoche (L)

7. Denard Span (L)

8. Jose Lobaton (S)

By any way you measure it, Bryce Harper is one of the best hitters on the Nationals; it's hard to argue against that. Even while playing through some injuries last season he had a better on-base percentage and slugging percentage than Zimmerman. It wasn't a huge advantage (23 points in on-base, 21 points in slugging) but it was still an advantage. Plus he's faster than Zimmerman, which isn't accounted for in wOBA. So either he or Werth would logically be considered the best hitter on the team.

Here was the lineup Williams ran out there against Mets starter Bartolo Colon:

1. Denard Span (L)

2. Anthony Rendon (R)

3. Jayson Werth (R)

4. Adam LaRoche (L)

5. Ryan Zimmerman (R)

6. Bryce Harper (L)

7. Ian Desmond (R)

8. Jose Lobaton (S)

From Adam Kilgore's story in the Washington Post on why Harper hit sixth:

"We want to continue to open Bryce’s game up," he said. When asked about what that meant, and why Harper needs to hit lower in the lineup in order open up his game, Williams expanded on his reasoning.

"One, I think it takes a little bit of pressure off of Bryce," Williams said. "It allows him to use his legs, and I think that’s important, when he wants to use his legs. Now, we look at tonight as an example. [Mets starter Bartolo Colon] is really quick to the plate, so will there be opportunities to do that? You never know. But we want to give him the option to do. ...

"Now, from a managers’ perspective you say 'If I hit him second or third in front of Jayson [Werth] and [Ryan Zimmerman], do I really want him trying to steal second when we're one swing away from a two-run homer or a three-run homer?' That's the logic. Most of all, I want him to be free and play and not have those boundaries on him. And I think, for me, over the long run he will drive in big runs for us."

OK, so from that we gather that Williams hit Harper sixth to take pressure off him and to possibly allow him to steal a base. Harper hit fifth on Opening Day, when the lineup went Span-Zimmerman-Werth-Wilson Ramos-Harper-Desmond-LaRoche-Rendon (also against a right-hander).

Look, managers obsess over lineups -- probably too much. But they are a little important, even if the gains from a statistically optimal lineup are small. Studies show that an optimal lineup would have your best hitters batting second and fourth. Williams hit his two best hitters sixth and third. Some of that could have been matchups. Maybe he thought LaRoche was a good matchup for Colon, or that LaRoche will bounce back from a bad 2013 (although he hit him seventh on Opening Day). It's possible that Williams wanted to go left-right-left, although he hit three righties in a row against Dillon Gee. Maybe he really does think a stolen base from the No. 6 batter is more important than having Harper get more plate appearances than Span. Maybe he thinks Harper doesn't "deserve" to hit third or fourth, in deference to his more veteran teammates.

The biggest flaw here is that Span is hitting leadoff and he's clearly one of the weakest hitters on the team. He's not terrible, so it's far from the worst lineups we've seen, but he doesn't bring a high enough on-base percentage to offset his lack of power (.279/.327/.380) and he's not a big enough base thief to create many extra runs that way (20 steals in 2013). He is, however, probably the fastest guy on the team and that's why he's hitting leadoff. So Williams has elected -- for now -- to give an inferior hitter more plate appearances.

For all the sabermetric advances in the game, such as the increased use of infield shifts, a lot of managers still use sub-optimal batting orders, failing to realize you're better off getting one of your best hitters higher in the order instead of worrying about having an RBI guy batting fifth or sixth. It's early, so I don't want to bash Williams too much here. Other than hitting Span first and Werth third, it appears he's going to move guys around. Harper is batting second in Thursday's game, although that may simply be because Danny Espinosa is playing instead of Rendon.

And bottom line: If Harper hits like most of us expect him to, he'll move up in the order. (I think.)