Rozner: Is it possible Cubs haven't played their best baseball?

When a team is playing above .700 baseball nearly 60 games into a season, with a run differential of plus-2.5 runs per game, it sounds ridiculous to think such a team could be better than it's been.

Welcome to the ridiculous 2016 Chicago Cubs.

There are actually ways the Cubs could get better this season, and you can be certain Theo Epstein is looking at the possibilities, ensuring the Cubs can weather whatever storm may hit the rest of the regular season and — specifically — what could potentially go wrong in the postseason.

As for the regular season, there will be slumps and there will be rough stretches. It's going to happen, but that's not really a concern.

Injuries on the pitching staff are always top of mind.

But the strength of this team is obviously its starting rotation, which went into Tuesday's outing in Philadelphia with baseball's best ERA (2.33), batting average against (.200) and OPS against (.564), to name just a few.

Three starters were in the top six in MLB in ERA (Jake Arrieta, Jon Lester and Jason Hammel) and the other two were 23rd (Kyle Hendricks) and 28th (John Lackey).

If they continue at this pace, they could post the best rotation ERA in the last 100 years.

Ridiculous.

And though it sounds odd to suggest, the Cubs could be even better.

Seriously, even while having by a mile the best run differential and having scored more runs per game than every team except Boston, the Cubs haven't really produced as much offensively as they might be able to if they can get a little more from a couple positions.

Anthony Rizzo is due for a big second half and is just starting to catch fire, while Jason Heyward hasn't even really started to help offensively. Look for both to produce more over the next four months.

The Cubs have to be thinking about a left-field bat.

Not that they've given up on Jorge Soler. Not at all. They believe in Soler — who's now on the DL with a hamstring issue — but the loss of Kyle Schwarber should not be minimized and is more glaring every day.

But as Epstein considers the ways in which he can tighten this up before the postseason, he might also be looking at the best available late-inning relievers, and what that could do for the Cubs in the playoffs.

Imagine being able to throw Travis Wood in the sixth, Pedro Strop in the seventh, Hector Rondon in the eighth or ninth, and Andrew Miller or Aroldis Chapman in the eighth or ninth.

The Cubs, who already have the best rotation in baseball, could shorten the game to five innings the way Kansas City has the last few years. That would be a frightening proposition for even the best competition out there.

Rondon has done nothing to put his job in jeopardy. In fact, it's not easy when your team is blowing everyone out and you're not getting much work, but it would be reasonable to wonder how some relatively inexperienced arms will react to unfathomable pressure.

There is also a cautionary tale in what the Washington Nationals did a year ago when they brought in Jonathan Papelbon at the trade deadline. Drew Storen had been nearly perfect as closer, but the eighth inning had been an issue and that would become Storen's new role.

It's not the reason the Nats fell apart in the final two months. It's more coincidence than anything else. Papelbon was good until it didn't matter anymore, though Storen was not as good as he had been before finishing his season in mid-September with a broken thumb after slamming the lockbox in his locker.

But this is about winning the World Series and nothing else, and if anyone can manage egos it's Joe Maddon, who has convinced his players that there are no individual goals or roles on this team that supersede winning the last game played in the postseason.

So if the Cubs can shorten the game by adding a huge bullpen arm, that's something Epstein has to seriously consider.

This is where we are. The pick here was the Cubs to win the World Series, and yet they're even better than anyone could have imagined, including the Cubs' front office.

And, still, they can be even better this season than they've already played.

Ridiculous.

brozner@dailyherald.com

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