The Boston Red Sox rotation began the season with some scrutiny as the starting five was filled with average to above average types and no pitcher resembling an ace. That scrutiny has turned to criticism as we near the end of the first month of the season and that rotation has allowed more runs than any other starting group in the American League and their 5.75 ERA is the worst in Major League Baseball. The rotation has gotten off to a terrible start, but the offense has produced and the Red Sox will still enter May with a winning record at 12-10. While a bloated ERA has generated calls for the Red Sox to make a trade for a starter, the current rotation has pitched better than its ERA would indicate. Going forward, the Red Sox rotation should get much better results than we have seen so far.

The Red Sox have given up a lot of runs, but the rotation’s FIP is a middle of the road 3.91. The Red Sox and Cleveland Indians are the only two rotations in MLB to have their ERA and FIP differ by more than one, and for the Red Sox that number is 1.84. The team’s walk rate at 8.8% is a little too high, but they make up for the high walk rate by striking out 22.9% of hitters. Their 14.9% K-BB rate is in the upper third of American League teams. Individually, there is not a single starter with a lower ERA than FIP.

In a more visual form:



Of the 118 pitchers with at least 20 innings this season, less than half (49) have a higher ERA than FIP in the early stages of the season. Clay Buchholz’s 3.11 difference is the second-largest in baseball, behind only former teammate Jon Lester. Justin Masterson is 15th, Joe Kelly is 20th, and Wade Miley did not make the list with only 15.2 innings, but his ERA-FIP is the biggest in the rotation. Rick Porcello is only 40th on the list, but his 1.69 home runs per nine innings is nearly double his career mark of 0.95. Porcello’s start last night where he went seven innings, gave up two hits, one run, and two walks while striking out six was certainly encouraging.

Wade Miley has been the most disappointing Red Sox starter. After trading Allen Webster, Rubby de la Rosa, and Raymel Flores to the Arizona Diamondbacks for Miley, the Sox signed him to a reasonable three year extension with a club option that contained around $20 million in guaranteed money. The transition to the American League can be a difficult one, and Miley has mixed in two adequate starts with two really bad starts where he was unable to make it out of the third inning. He currently has more walks than strikeouts, but he has not lost velocity and his pitch mix is similar to the rest of his career.

Like Miley, Clay Buchholz and Rick Porcello appear to be throwing with the same velocity and the same mix of pitches. Justin Masterson has lost some velocity, but is attempting to counter that loss by throwing his slider more. As Carson Cistulli wrote, Joe Kelly has gone the other way, gaining a little velocity, but he is also throwing a slider more and has gotten great results in limited use with a 24% whiff rate, per Brooks Baseball. Kelly is striking out 29% of hitters so far this year. That number is not likely to remain that high, but his ERA should get better as the year progresses. For the entire rotation, the projections see better days ahead.

The chart below compares the pitchers’ current ERA with their projected ERA and FIP from the rest of the season from FanGraphs Depth Charts.

Every Red Sox starter should get better results than what they have shown thus far. While their .308 BABIP is slightly unlikely and there is nothing too unusual about their 11% HR/FB rate, where the Red Sox have been hurt the most this season is in sequencing.

The Red Sox current left on base percentage for starters is 59.3%, worst in the league. That number is bound to move up, and with it the runs will go down. Since 2010, the single worst seasonal LOB% was put forth by the Cleveland Indians in 2012, when they ended the year with a 65.3 LOB%. Over the five previous seasons, here are the worst rotations in April by LOB% and where they ended up at the end of the year.

Year Team April LOB% Season LOB% Change 2010 Pirates 59.9 66.3 6.4 2011 Cubs 64.5 69.4 4.9 2012 Twins 62.3 67.0 4.7 2013 Athletics 64.6 73.8 9.2 2014 Diamondbacks 61.4 69.6 8.2 AVERAGE 62.5 69.2 6.7

Every single team moved up, showing that their April results were somewhat of an aberration. The Red Sox do not have a great rotation, but that was their plan entering the season. The rest of the season positional rankings based on projections have the Red Sox with the 24th best rotation in baseball which is the same spot the Red Sox were in entering the season. The team knew when it did not bring back Jon Lester or sign another big-name free agent like Max Scherzer or James Shields that this was the team they planned on. They chose to spend their money on Pablo Sandoval and Hanley Ramirez so they can could try to pummel the opposing pitching staffs and hope that a low-ceiling, stable rotation would put them in contention.

Despite poor results from the pitching staff, their plan has worked. Only the Blue Jays have scored more than the Red Sox 113 runs this year. While the .318 wOBA and 98 wRC+ are in the middle of the pack, the team’s .272 BABIP is bound to improve. The Red Sox have a winning record and sit just one game behind the New York Yankees for first place in the AL East. Their odds to win the division are nearly double that of any other team in the East at 47%. They are currently projected to win 88 games which is three games ahead of the Yankees and six games ahead of the Tampa Bay Rays and Toronto Blue Jays. If the Red Sox rotation fails to stabilize as the season goes on, they have the resources to make a big move, but for the moment they might be better served to see what they really have before rushing to judgment.