Why the Cubs' hot stretch will (or won't) last

When the calendar flipped to August, one game separated the Chicago Cubs from the San Francisco Giants in the NL wild-card race, with the Cubs looking up at the Giants in the standings. Just 26 days and one 21-4 stretch later, the Cubs have put the team they face Wednesday night in San Francisco far in their rearview mirror and opened up a 7 1/2 game lead for a playoff spot. Is Chicago’s torrid stretch sustainable, or are the Cubs due to cool off soon?

Why the Cubs will keep it up:

Chicago’s offense has depth: Missing right fielder Jorge Soler hasn't slowed the Cubs down, as they are 2-0 since his injury. With the return of infielder Tommy La Stella, who had a walk and RBI hit Tuesday to go along with the solid all-around play of Chris Coghlan, the Cubs have enough to sustain a slump or two. Since the All-Star break, they've had a myriad of different players get hot at the plate. It’s not just one or two guys inflicting damage.

Top-end starters: Unless a career high in innings catches up with Jake Arrieta the Cubs aren't prone to long losing streaks with him and Jon Lester at the top of the rotation. Even when Lester has had down moments lately, they don’t last long -- as evidenced by his 8 2/3 innings pitched on Monday following his shortest stint as a Cub. The team has two slump busters in their rotation.

Joe Maddon: It sounds like a clich√©, but the Cubs' manager simply knows what buttons to push, no matter the situation. That could mean pulling a starting pitcher early, resting a regular at the right time or just backing off batting practice and early work. The Cubs aren't prone to long losing streaks in part because Maddon has his pulse on it all. Somehow, someway, he’s pulled them out of any little losing skids before they’ve become big ones.

Why they won’t:

Youth: It certainly doesn't feel like it’s coming, but it’s not out of the realm of possibility that the Cubs’ young hitters hit a September wall. Could they all slump at once? Stranger things have happened. Several have never played this many games in a season, which presents a challenge they've simply never had before.

Bullpen implosion: Every so often, you see cracks in the middle to back end of the bullpen. Overuse of high-leverage guys Pedro Strop and Hector Rondon is a concern, as is the injury to Jason Motte that had the Cubs adding a fourth lefty reliever to the mix. That’s not ideal. Newcomer Tommy Hunter has given up some hard hits and has an ERA of 6.00 since being acquired. There’s enough little things there that will keep some focus on the relievers.

The Schedule: The Cubs play 12 games in the final month against St. Louis and Pittsburgh, two playoff-tested teams ahead of them in the standings. One stretch includes 10 straight on the road with six coming against those two teams. In fact, 18 of the Cubs' final 28 games are played away from Wrigley Field. That could be an obstacle as bodies get worn down. The good news is the Cubs currently have the best road record in the majors.