The Pirates’ mistakes in Sunday’s game were obvious.

Coming into the bottom of the seventh with a 3-1 lead, starter Ross Ohlendorf walked Mike Fontenot, the leadoff batter.

After two flyouts, second baseman Bobby Crosby narrowly missed fielding a grounder for the third out. Reliever Evan Meek made a wild pitch that scored a second run, and then shortstop Ronny Cedeno made an outright error that allowed a third run to score.

In the eighth, an Alfonso Soriano single, followed by wild pitch and a second single by pinch hitter (and former Pirate) Xavier Nady scored the winning run.

This prevented the Pirates from making a rare sweep of the Cubs at home and extend their victorious string in the season series to six.

The Pirates who were 11-0, are now 11-1 when leading after six innings.

That’s a very good record, except that the Pirates haven’t been leading after six that many times, and often not by much. Yesterday, “bad luck” caught up with them.

What was unspoken in yesterday’s game was the below-average run production. The club scored only three runs, all of which came in the second inning.

Two hits and two walks loaded the bases while pushing in a run. The third hit of the inning scored two runs. That sequence accounted for half the Pirates hits, half their walks, and half their baserunners for the WHOLE game.

Besides that, only in the seventh did the Pirates have more than one man on base (loading the bases, but without scoring). The Cubs got eight hits, four walks, and four runs altogether, enough to edge out the Bucs.

One way of looking at things is sequentially.

The Pirates WERE ahead 3-1, and then blew the game by allowing two runs in the seventh inning and one in the eighth. If they hadn’t done so, they would have won.

Another way of looking at things is quantitatively: the Chicago Cubs scored four runs over a nine inning stretch, the Pirates only three.

The order of the innings could have been reversed.

The Cubs scoring two runs in the second, the Pirates’ three in the top of the seventh, and the Cubs again in the bottom of the seventh, for a 3-3 tie, and the winning run in any given inning, with the same result.

On the season, the Pirates have scored only 131 runs, ahead of only the Houston Astros in the National League. They are lucky not to be the second-worst team in the league (or even worst, because the Pirates have also allowed more runs than the Astros).

In their 16 wins, the Pirates have scored 90 runs, or an average of more than five-and-a half runs apiece. In their 21 losses they’ve scored only 41 runs, averaging just under two runs apiece.

They scored only three runs yesterday. That’s closer to a two run loss than a five-and-a half run win.

The magic number is four: The Pirates are likely to win when they score four or more runs. They are likely to lose when they score fewer.

To illustrate, let’s look at Saturday’s game, which was 4-3 the other way.

After successive relievers had put down Cubs batters in order without difficulty, the Pirates were leading 3-2 coming into the ninth, then scored a badly needed insurance run on Jeff Clements’ solo homer.

In the bottom of the ninth, Octavio Dotel, who was charged with closing the game, allowed a walk to Starlin Castro, then a triple to Kosuke Fukudome to make the score 4-3 with only one out.

Fortunately, Dotel struck out the next batter, Ryan Theriot, preventing the runner from advancing, then fanned the following one, Marlon Byrd, to end the game for the Pirates’ victory.

Coming into their portion of the ninth on Saturday, the Cubs had only a nine percent chance of winning (based on historical results for home teams trailing by two coming for “last licks”).

But that percentage shot up to 42 percent on the triple, before declining to zero on the remaining two outs. (The Cubs were actually favorites to score the runner on third, which would have made the game a toss-up).

Coming into bottom of the seventh with a 3-1 deficit yesterday, the Cubs had a 22 percent chance to win. The walk made it 28 percent, the wild pitch and first run, 33 percent, and the second run created an even-money bet.

The Pirates could have won yesterday’s game.

They could also have lost Saturday’s.

On the whole, winning one of those two was a “fair” result, given their batting. In order to do better, they need to hit better and score more runs.

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