The Chicago Cubs will officially welcome Daniel Palencia back to the bullpen. The organization reinstated the closer on Sunday afternoon ahead of their 1:20 matchup with the Arizona Diamondbacks. To make room on the active roster, they will designate Yacksel Ríos for assignment. The righty was called up last week on the same day Riley Martin was placed on the 15-day IL. Ríos only went on to appear in a single game for Chicago, throwing 1.2 innings of scoreless work against the Dodgers with two strikeouts. It was only two days ago that the Cubs received some positive news on their flame-throwing arm. Palencia was healthy enough to suit up for a rehab appearance with the Iowa squad. While he only stayed in the game for two outs, 14 of Palencia's 19 pitches were strikes. He also recorded one strikeout, which came on a 102 mph called strike in the bottom of the zone. In other words, it feels safe to say he's feeling healthy! One of the hardest throwers in baseball returns at a scary time for the NL Central.…