With mechanic tweaks, Justin Masterson expects to be a starter

High socks are back in fashion in Boston. The man bringing them back is a familiar face.

The Red Sox introduced pitcher Justin Masterson, who the Red Sox traded in 2009 as the centerpiece in the Victor Martinez trade at the deadline, during a conference call with the media on Friday. Masterson will earn $9.5 million in base salary in a one year deal with additional incentives that could bump the value of the contract up to $12 million based on the number of innings he pitches. He can earn an additional $500,000 for surpassing thresholds of 185, 190, 195, 200 and 205 innings pitched.

Masterson turned in a poor 2014 season while splitting hist time between the Cleveland Indians and the St. Louis Cardinals en route to posting the 14th lowest wins above replacements (0.3) and the 19th worst FIP among starters with at least 120 innings pitched (128 qualified pitchers). Masterson said the poor performance stemmed from a combination of poor health and mechanics. Amidst his recovery from an oblique strain in late 2013, Masterson developed bad habits mechanically which, combined with a right knee injury that developed as a result of remaining scar tissue from his oblique strain, resulted in a major drop in velocity.

"We tried to make corrections through mechanical type things because I wasn't experiencing any pain, but I lost some flexibility and, quite honestly, a lot of other things," Masterson said. "I'm 100 percent confident we'll be good to go. I feel in a great spot now. I have confidence this will probably be one of the best seasons I've ever had."

"2014 was a bit of a battle," said general manager Ben Cherington. "He battled through some things that may have affected his ability to do some things on the mound that he was accustomed to doing, to get to points in his delivery that he had always done.

Throughout his career, Masterson averaged 92-93 mph on his fastball, 90-92 mph on his sinker, 82-84 mph on his slider and 84-87 mph on his changeup. In 2014, Masterson saw velocity drops in all of his pitches except his changeup. His fastball averaged in at 90.3 mph, sinker at 88.5 mph and slider at 80.9 mph. Masterson's velocity drop had a lot to do with the poor habits he developed mechanically according to one scout.

Lets take a look at Masterson's windups in 2013 and 2014.

On the outset, there isn't much different in Masterson's windup (besides the difference in camera angle). Masterson still swings his arm around like a whip while delivering the pitch to the plate and his socks are as high as they were when the righty came up through the Red Sox farm system. There is one crucial difference, however. Let's take a look at Masterson's windup base.

Here is Masterson's base from 2013, when he threw 93-94 mph.

Here is Masterson's base from 2014, when he was getting about 89-90 mph consistently on his fastball.

Pitcher develops torque from the base of their windup. Torque is the reason why Tim Lincecum was able to throw in the high 90s during his early days. It's why Pedro Martinez threw hard and was so dominant, despite his size. Masterson's knee injury debilitated his ability to generate torque in his windup, as seen in the disparity in the drive off the rubber in the GIF from 2014.

If manager John Farrell and pitching coach Juan Nieves are able to fix up Masterson's mechanics and recoup some of his old velocity, a bounce back in 2015 is incredibly feasible. The precipitous drop in velocity came suddenly for Masterson and was neither gradual nor expected (given his age). During his tenure as a starter with the Indians, Masterson never saw a drop in average velocity off his fastball of more than 0.5 mph from year to year.

In addition, the only significant changes in his pitch usage in 2014 came with the slider. In 2013, Masterson used his slider 26.9 percent of the time. In 2014. that percentage fell to 18.9 percent. That drop comes with an asterisk, however, as Masterson's slider usage in 2013 deviates off of his career norms (although it's interesting to note that Masterson's career-best strikeout rate coincided with the increase in slider usage).

The Red Sox stated on Friday that they view Masterson as a starter in 2015. Getting Masterson back to his 2013 form (3.5 WAR) will be crucial in maximizing the 29 year old's value.

"That's the role we expect [Masterson] to be in," Cherington said. "If he's what we think he will be in 2015, he'll be a good one."

There is a clear mission in Masterson's mind.

"If I pitch the way I'm supposed to," Masterson said, "I will be a starter."