The Cincinnati Reds have done a good job lately of trading excess parts for parts they need. Over the weekend, the Reds acquired starting pitcher Mat Latos and while they did give up a lot, they were trading from excess. The Reds traded from excess again today, this time, acquiring a much needed reliever.

The Reds acquired LHP Sean Marshall from the division rival Chicago Cubs for LHP Travis Wood and two minor leaguers. This is another solid acquisition for Reds GM, Walt Jocketty.

Over the past three years, there haven’t been too many relievers as good as Marshall. Since 2009, Marshall 2.73 xFIP (better than Mariano Rivera‘s, Jonathan Papelbon‘s, and Brian Wilson‘s), 9.6 K/9, and a 55.4 percent Ground Ball Percentage in 189.1 innings. His 5.4 WAR is fifth amongst all relievers in that time frame.

What makes Marshall special, is that there is no huge difference between his righty and lefty splits. Yes, Marshall fares better against left-handed batters (what lefty doesn’t?), but he can get a right-handed batter out in a big spot as well. Marshall has held left-handed batters to a .633 OPS throughout his career and right-handed batters to a .733 OPS. Not a big difference.

Marshall should settle in nicely in the Reds’ bullpen in 2012. The Reds currently don’t have an official closer yet for 2012, so Marshall could be that guy. However, I do see Marshall being the eighth inning guy to Aroldis Chapman in the ninth.

Marshall is a free agent at the end of the 2012 season.

In return for Marshall, the Cubs will get 24-year-old Travis Wood. Wood has a 4.18 ERA, 7.0 K/9, 2.8 BB/9, and a 31.4 Ground Ball Percentage in 208.2 Major League innings. Perhaps Wood’s claim to fame was his pitching duel with Philadelphia Phillies’ ace Roy Halladay on July 10th, 2010.

Wood matched Halladay pitch for pitch and had a perfect game going into the ninth inning. Carlos Ruiz led off the ninth with a double, which ended Wood’s perfect game bid, but Wood was pretty darn awesome that night.

The Cubs are clearly in rebuilding mode because there is no way a team would trade a pitcher of Marshall’s caliber to a division rival if they thought they would be competing for a playoff spot anytime soon. Wood will fill a piece of Theo Epstein’s puzzle as a serviceable No. 3 or 4 starter. That’s probably his ceiling.

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