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The Boston Red Sox have reached an agreement with free-agent starting pitcher Justin Masterson.

MLB Roster Moves reported the deal is official:

Buster Olney of ESPN initially confirmed the signing:

Rob Bradford of WEEI reported the terms of the agreement with Masterson:

Fox Sports' Ken Rosenthal provided details on the incentives:

Masterson entered the 2014 season with a chance to make himself one of the league's most coveted free agents by putting together a second straight strong campaign. Instead, he couldn't shake off a number of injuries and proceeded to post the worst numbers of his career.

The 29-year-old starter went 7-9 in 28 games split between the Cleveland Indians and St. Louis Cardinals. The latter acquired him at the trade deadline with hopes he could provide a spark to the rotation. He posted a 7.04 ERA in nine games after the deal for a season mark of 5.88.

Just one year earlier, however, it looked like a new Masterson was emerging. He significantly improved his strikeout rate (9.1 K/9) and that equated to a more appealing 3.45 ERA and 1.20 WHIP.

They are hoping he can return to that level in 2015, which would make it a value signing. Staying healthy would go a long way in helping Masterson make that happen.

Patrick Mooney of CSN Chicago passed along comments from the right-hander as he prepared to hit the market and stated he was feeling better.

Coming off a subpar year and dealing with some injuries, it's been nice (thinking) now I'm in a really good spot. I feel great. I haven't been able to get in many games, but I finally feel good. Being able to take that into the offseason, I think that's more exciting than where I may or may not end up.

Masterson has dealt with a lingering knee issue to go along with shoulder and oblique injuries.

The biggest problem last season, aside from those injuries, was an increase in walks. His walk rate jumped considerably (3.5 per nine in 2013 to 4.8 in 2014), which when paired with lower strikeout numbers got him into trouble quite often.

That said, the advanced numbers say his 2014 wasn't as bad as the 5.88 ERA suggests. His FIP was 4.50 and his xFIP was 4.08, via Fangraphs, with factors such as his left on-base percentage and batting average on balls in play suggesting a bounce-back is quite possible.

Of course, even a 4.08 ERA wouldn't be anything to write home about in a time period where the game is shifting back toward the pitchers. But if Masterson can improve his control along with a normalization of those other numbers, he would be a solid member of the rotation.

It's a relatively low-risk move that could pay off nicely in 2015.