A cursory glance at the Cubs bullpen depth chart is all it takes to question if they have a reliable left-handed reliever.
Mike Montgomery is the first guy that jumps out, but he fills the role as the long relief option in the Cubs bullpen and is one injury away from re-joining the starting rotation. He also wasn't very good as a reliever last year, posting a 5.13 ERA, 1.44 WHIP and 5.5 K/9 in 26.1 innings out of the bullpen.
Brian Duensing is also projected to make the Cubs' Opening Day roster since he's under contract for $3.