Olney: The X factor of every playoff team heading into October

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A rival executive said recently that he feels as if Los Angeles Dodgers manager Dave Roberts has continued to improve in his role, gradually constructing more assertiveness on top of his relentless good nature. As he wins more games and the Dodgers promote more buy-in from players drafted and developed under Andrew Friedman, Roberts has piled up credibility.

And he might need it, if the Dodgers' greatest uncertainty manifests itself in October. Kenley Jansen is the team's great X factor for the postseason: When he's at his best, his velocity reaches 94 mph and his cutter cuts, and Roberts can confidently call on him believing he will shake Jansen's hand in a victory line at night's end.

But at his worst, Jansen struggles, as he did from time to time during the 2019 season. Jansen's ERA of 3.71 is a career worst. He has given up nine homers in 62 innings this season, the second most in any year of his 10-year career. Opponents have put up a .383 slugging percentage against him, pretty good among most relievers -- but Jansen is the closer of a team with aspirations of winning its first championship in 31 years.