Offense, pitching, bad luck contributed to Cubs’ 4-10 stretch

The last two weeks have been tough on the Cubs, who were 51-30 before their 10-4 victory Monday against the Reds after standing 47-20 through games of June 19.

A 4-10 stretch is nothing to panic about. Bad streaks happen. Last season, the Cardinals went through a 5-9 stretch starting May 9 during a 100-victory season, and the World Series champion Royals endured a 2-9 stretch starting May 24.

Still, we can take a by-the-numbers look at what went wrong for two weeks through the series against the Mets that ended Sunday.

Starting with the Cardinals’ three-game sweep June 20-22 and ending with the Mets’ four-game sweep Thursday-Sunday, the Cubs averaged 4.2 runs. In their first 67 games, they averaged 5.4 runs.

The Cubs’ batting average during their 4-10 run was .239. That was well below their season average of .254, but most of the difference was in batting average on balls in play. Normal BABiP is about .300, and the Cubs are at .302 for the season. But they were only at .284 from June 20-Sunday. That suggests they were hitting in some tough luck.

Their on-base percentage was down from .346 overall to .326 and their slugging percentage from .432 overall to .427. Both were affected by the drop in batting average and BABiP, though their walk rate dipped to 9.9 percent of plate appearances, compared with 10.9 for the season.

The Cubs also were swinging at more pitches outside the strike zone, something that might have been the result of hitting behind in more counts. Their two-week average of swings on 32.4 percent of pitches outside the zone was up from their season average of 27.5 percent, according to Fangraphs.com.

And while the Cubs scored a run per game less than their season average during their 4-10 stretch, they also gave up two runs per game more. Their two-week ERA of 5.43 was several giant steps back from their season ERA of 3.11.

Starters had a 6.09 ERA during that stretch and averaged just more than 5⅓ innings per start. Their season averages are a 2.88 ERA and just less than 6⅓ innings per start.

Some increase in ERA was to be expected among the starters, with a full-season FIP (fielding-independent pitching) of 3.60. But this was no simple regression to the norm. Their two-week FIP of 6.78 was in truly awful territory.

That put extra pressure on a bullpen that turned in a 14-day ERA of 3.99, as opposed to 3.61 for the season.

Keep in mind that in a stretch as short as two weeks, implosions such as 14-3 and 10-2 losses to the Mets will have a disproportionate effect on a statistical snapshot. Five of the 14 games were decided by one run, with the Cubs going 1-4 — a 5-4 victory, three 4-3 losses and a 3-2 loss. Chance and a low BABiP play a role in such games.

No two-week stretch should be taken as signaling a team’s fate. But hitting and pitching both contributed to the Cubs’ slide.

Follow me on Twitter @GrochowskiJ.