Getting ahead early sends win expectancy soaring

A team that leads at any point in a major-league game wins more than half the time, even if that lead is only a single run in the first inning.

In the first month of the season, the White Sox (13-10 through Sunday) were about average in getting a first-inning jump. They scored in the first eight times and allowed first-inning runs eight times.

On the other hand, the Cubs (13-11 through Sunday) were in an early hole much more often than they’d like. They scored in the first seven times and allowed first-inning runs 12 times. No other team had given up runs in the first in half its games, and only five others had done so in 40 percent of their games or more.

And the Cubs aren’t just falling behind 1-0. They’ve allowed 28 runs in the first, an average of 2.33 for each opening inning in which the opponent has scored or a major-league-worst 1.17 runs per first overall. The White Sox are more than a half-run better at 0.65 runs per first.

For a look at how much difference it makes to fall behind early, there’s a win-expectancy finder at https://gregstoll.dyndns.org/~gregstoll/baseball/stats.html#H.-2.1.0.1. It draws on a database of all games played from 1957 through 2015 and tells us how often teams have won in any given situation.

At the start of a game, the home team has a win expectancy of 53.91 percent. When the visitors have scored one run in the first, they’ve gone on to win 51.76 percent of the time. If it’s the home team that takes a one-run lead into the top of the second, its chance of winning rises to 64.4 percent.

Visitors have won 62.04 percent of the time when leading by two runs after a half-inning and 70.38 percent of the time when leading by three. Home teams have won 74.13 percent of the time when leading by two after a full inning and 81.76 percent of the time when leading by three.

That multi-run effect is one reason sacrifice bunts early in games have declined. Successful sacrifices increase chances of scoring one run but decrease chances of scoring multiple runs, and those multi-run early innings send win expectancy soaring.

The Cubs went 5-5 in April when allowing more than one run in the first. Starters Jake Arrieta (14.40), John Lackey (12.60), Kyle Hendricks (10.80) and Brett Anderson (9.00) all had first-inning ERAs of 9.00 or higher, and Jon Lester was at 3.60.

The Sox played fewer such games, going 1-3 when allowing multi-run firsts.

The Cubs were much more successful in limiting early damage last season, ranking third in the majors with runs allowed in 23.46 percent of first innings and tied for fourth with 0.41 runs per first. The Sox were 16th at 32.1 percent of firsts but eighth at 0.51 runs per first.

For the Cubs, bringing those first-inning runs back down is looking like a key to having their win expectancy climb back up.

Follow me on Twitter @GrochowskiJ.