The Zack Greinke sweepstakes appeared to have been just a three-team race so far, between the Los Angeles Angels, Los Angeles Dodgers and Texas Rangers. Now, a fourth suitor has emerged -- the Washington Nationals.

CBS Sports' Jon Heyman mused that the Nationals could be the Dodgers' biggest threat to sign Greinke, and not that Rangers or Angels. Washington acquired Denard Span from the Minnesota Twins on Thursday, and as Heyman notes, it means that Washington will not have to shell out money to sign Michael Bourn, or another free agent centerfielder.

The deal also means that the Nationals will say goodbye to Adam LaRoche, as Michael Morse is now penciled in as the team's starting first baseman.

With money to spend, and an owner with deep pockets, the Nationals could very well be a major player in the Greinke sweepstakes. At the least, Washington's interest should drive the price up for either Los Angeles team, and for the Rangers.

If the Nationals do land Greinke, they would boast a rotation featuring Stephen Strasburg, Gio Gonzalez, Greinke, and Jordan Zimmermann, and would have to considered one of the favorites to capture the pennant in 2013 -- just one year after a heartbreaking loss to the St. Louis Cardinals.