I hate interleague play. Two reasons: one, it creates matchups no one cares about, like Marlins-Mariners, as a gimmick to get three or four interesting matchups in the entire majors, and two, it creates an imbalance among the schedules of teams competing for the same playoff spot (I don't like the use of unbalanced schedules with a wild card system for the same reason). And that's what I'd like to discuss today, with a 12-game set of interleague games coming up in the next two weeks between the NL East and the AL West. However, there's a disconnect. Because the AL West only has four teams, one team in the NL East is playing an NL Central team during each series, and miss one of the AL West teams.
Mets -- miss Texas, play Houston
Phillies -- miss LA/Anaheim, play Milwaukee
Marlins -- miss Oakland, play Chicago Cubs
Braves -- miss Seattle, play Cincinnati (4)
And our Nats are the lucky team that gets to play all four AL West teams. So who has an advantage here? I ran the numbers with a quick and dirty methods, using two major variables. The first is the record of the opposition, and the second is the home/away factor, using the MLB figure this season -- a .580 home team winning percentage. This isn't that much -- less than half a win per 6 games, the length of the interleague homestands (All NL teams are at home versus AL teams this week, then it reverses next week).
Here are the schedules for reference (marked by HOME and away), with average opponent winning percentage (as of Monday morning) at home and on the road listed (The Braves' road schedule is weighted because of the 4 games versus Cincinnati).
Mets -- HOU, LAA (.477 home), oak, sea (.435 road)
Phillies -- TEX, MIL (.523), sea, oak (.435)
Marlins -- SEA, TEX (.509), chc, laa (.558)
Braves -- LAA, OAK (.491), tex, cin-4 (.464)
Nationals -- OAK, SEA (.435), laa, tex (.577)
Next, I took the home and road winning percentages, multiplied by 6 games per series (or in the one case, 7), then made the home team adjustment, .48 wins per 6 games (or 1.07 wins per 7 games). This left the following indexes (based on a scale of predicted wins based on schedule strength based on 12 games.
Mets -- 3.62 home, 2.61 road, 6.53 total
Phillies -- 3.34 home, 2.91 road, 6.25 total
Nationals -- 3.87 home, 2.06 road, 5.93 total
Braves -- 3.59 home, 2.68 road, 6.27 total in 13 games (prorated to 12: 5.78)
Marlins -- 3.43 home, 2.18 road, 5.61 total
Subsituting punchless Houston for Texas, and giving the Mets the weakest opponents on the road gives them the advantage. As for the Nats, they need to take advantage of their major home advantage, because the road trip to LA/Anaheim and Texas will not be kind to them. And don't feel bad for the Marlins. They're already 3-0 in interleague, with 3 more to play against their "natural rivals", the Tampa Bay Devil Rays.