David OrtizDavid Ortiz and the Boston Red Sox have agreed to a one-year contract extension through the 2015 season with a club/vesting option for 2016 and a club option for 2017, the team announced Sunday night.

“With this agreement, we have near certainty that David Ortiz will finish his career in a Red Sox uniform, which is something we have all wanted and that we are all proud of,” said Principal Owner John Henry. “It is difficult to describe David’s contributions to our city both on the field and off the field, and we are so proud to have this ambassador of our game with us as he continues on this road to Cooperstown.”

The extension, which was first reported by ESPN.com’s Gordon Edes, will add a year to the two-year, $30 million (after incentives) deal Ortiz signed with the Red Sox last offseason. Ortiz will earn $16 million in 2015 under the extension, a source told WEEI.com’s Rob Bradford.

The Red Sox reportedly will announce Ortiz’s deal Monday.

Ortiz’s extension isn’t shocking. Multiple reports out of Fort Myers this week indicated that Ortiz and the Red Sox were closing in on a deal. Ortiz’s agent, Fern Cuza, reportedly was in Fort Myers on Sunday to meet with Red Sox officials.

Ortiz is coming off a strong 2013 season in which he batted .309 with 30 home runs and 103 RBIs in 137 regular-season games. The 38-year-old also enjoyed another strong postseason that was capped by an historic World Series performance against the St. Louis Cardinals.

Ortiz, who signed with the Red Sox as a free agent before the 2003 campaign, is entering his 12th season with the organization. The nine-time All-Star was slated to become a free agent after this season, although both he and the Red Sox expressed a desire this spring to continue their relationship beyond 2014.

Now that Ortiz’s deal has become official, the Red Sox can turn their full attention to Jon Lester, who on Friday expressed optimism regarding his contract discussions with Boston.

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