CHICAGO -- The Cubs clinched a postseason berth Wednesday night for the fourth time in four seasons. The accomplishment, as well as Albert Almora Jr.s walk-off single in the 10th inning, somewhat masked one of their biggest uncertainties moving forward -- their bullpen.
The Cubs have been without de facto closer Pedro Strop since he went down with a left hamstring strain on Sept. 13. On most days before getting hurt, Strop filled the vacancy left by closer Brandon Morrow, who's been on the disabled list since July 18 and is officially out for the year.

In their absence, the Cubs have relied on matchups to get through the later innings, often using different relievers at different times depending on the game and situation. Without having set roles, Cubs relievers always have to be ready to go, regardless of the inning.
"I just plan on every day being the first guy," right-hander Jesse Chavez said. "That's just my niche, my mentality being a long guy most of my career. You've just got to be prepared for when the phone rings the first time or the time it rings last."
Chavez was the first reliever called upon in Wednesday night's 7-6 win over the Pirates. He pitched two scoreless innings, the sixth and seventh.
It's true Chavez has been a long man throughout his career, and many times this season he's been the first reliever in the game. But the 35-year-old righty has also been used to shut down opponents in later innings since the Cubs acquired him in mid-July.
So naturally, a night after he threw 33 pitches as the first man in, Chavez served as the closer for the Cubs' 3-0 win over the Pirates on Thursday. He worked around a two-out single while throwing 16 pitches to earn his fifth save of the season.
During his time this season with both the Rangers and the Cubs, Chavez has appeared in the fifth, sixth, seventh, eighth and ninth innings.
"You've just got to get ahead in those situations," he said. "That way, it doesn't put more pressure on if the phone rings for the other guy."
Indeed, when teams are forced to rely on favorable matchups to get them through the later innings, poor execution from one reliever can alter the way the rest of the bullpen is used.
Of course, this can happen when the entire bullpen is available, but there is less room for error when the two most effective closers are injured.
Fortunately for the Cubs, they do have two healthy relievers who have been closers in previous seasons -- Justin Wilson and Steve Cishek.
However, both Cishek and Wilson have been shaky at times down the stretch, with Wednesday's game being the latest example.
Cishek recorded the final two outs of the eighth inning, but he walked two and allowed one costly single that brought home two runs. Both runs were charged to C.J. Edwards, who started the inning. Wilson allowed two runs on three hits in the ninth and was charged with the blown save. Edwards responded on Thursday night by inducing a huge double play in a scoreless eighth.

Manager Joe Maddon said that despite the 76 games Cishek has pitched in this season -- prior to Thursday's game -- his recent woes could be because of too much rest.
"He has been off just a click," Maddon said. "He's used to pitching more often. I know you look at the number of times he's been out there, and you think maybe all of a sudden that's why. But sometimes, it's because they haven't pitched in a while."
Maddon, however, went right back to Cishek on Thursday. In his 77th game this year, Cishek pitched a perfect seventh inning with one strikeout. 

Cishek said he's been trying to balance getting enough work in while also getting adequate rest so he's ready for the postseason.
"I felt a lot better today than I did in the previous couple outings," Cishek said Wednesday night. "It may not be as pretty, but it goes a long ways mentally knowing that I'm almost right there."