The Cubs have officially signed Edwin Jackson, the team announced. It's a four-year contract worth $52MM, and it does not include a no-trade clause. Jackson is a Legacy Sports Group client.

The Cubs have worked exceptionally aggressively to add free agent starting pitching this offseason. They already signed Scott Feldman, Scott Baker and Carlos Villanueva to join a rotation led by Matt Garza and Jeff Samardzija. Travis Wood also has considerable experience starting, but he might now project as a reliever.

None of the Cubs' additions will cost the team a future draft pick. The Nationals declined to make Jackson a qualifying offer after the season, which means he wasn’t linked to draft pick compensation. As MLBTR's Transaction Tracker shows, Jackson's deal represents the largest free agent contract the Cubs have agreed to under GM Jed Hoyer.

Jackson joins his eighth MLB team and his seventh club since 2008. The 29-year-old spent the 2012 season with the Nationals, posting a 4.03 ERA with 8.0 K/9, 2.8 BB/9 and a 47.3% ground ball rate in 189 2/3 regular season innings. He reached the 180-inning plateau for the fifth consecutive season with an average fastball velocity of 93.5 mph.

Jackson joined Legacy Sports in July, leaving the Boras Corporation. Last winter Jackson obtained a one-year, $11MM contract to play in Washington. One year later, the Indians, Rangers and Padres were among the teams with interest in Jackson.

Jackson ranked seventh on MLBTR’s list of top 50 free agents. As MLBTR's Free Agent Tracker shows, Kyle Lohse and Shaun Marcum are among the top free agent starters remaining.

Patrick Mooney of CSNChicago.com first reported the agreement while Jon Heyman of CBSSports.com added details (Twitter links). Mike Axisa contributed to this post. Photo courtesy of USA Today Sports Images.