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Cubs starting pitcher Marcus Stroman has been activated from the injured list in front of the Cubs' series against the Diamondbacks in Arizona beginning Friday night. It comes as a bit of a surprise, though the Cubs and Stroman had been pretty secretive on his progress from a rib cage cartilage fracture. 

Given that the Cubs activated Stroman before a Justin Steele start and demoted reliever Daniel Palencia as a corresponding move, it appears the Cubs plan to use Stroman out of the bullpen, at least initially. 

Stroman, 32, was having a career year for a bit this season, earning his second All-Star Game selection. Through 16 starts, he was 9-4 with a 2.28 ERA. He had several bad outings after that and then was shelved with a hip injury. Just as it looked like he was ready to return from that ailment, Stroman was diagnosed with the aforementioned rib fracture on Aug. 16. Due to the rarity of the injury among major-league pitchers, neither the Cubs nor Stroman himself could give any sort of timeline as to a potential return. 

Now that he's back, it'll be interesting to see how the Cubs proceed with Stroman. The rotation is currently Cy Young contender Steele followed by veterans Kyle Hendricks and Jameson Taillon along with youngsters Javier Assad and Jordan Wicks. The best guess is the Cubs find spots to give Stroman an extended warm-up (like he's starting the game) and then work multiple innings, as if he's building himself back to being a starter while on a minor-league rehab assignment. 

Should everything work out well, perhaps Stroman can rejoin the rotation before the end of the season or even for the playoffs, should the Cubs hold down their spot. For now, though, he'll likely be handled with kid gloves and rightfully so coming off such an odd injury.