Red Sox surge behind strikeout

Right-hander Ryan Dempster is striking out 12.9 batters per nine innings this season for Boston. AP Photo/Winslow Townson

In most years, seeing that the Boston Red Sox had the best record in the American League East and the top run differential in baseball at the end of April would come as little surprise. After all, the Red Sox have won two World Series titles in the last decade and annually find themselves in playoff contention.

But 2013 isn't most years, because rarely are the Red Sox coming off a season in which they lost 93 games and suffered national embarrassment on a regular basis. Most observers expected the Red Sox to rebound somewhat from last year's debacle -- if only because key players would return to health and Bobby Valentine would be anywhere other than Boston -- it's safe to say that few expected the club would be among the class of baseball after the first month.

While the Red Sox have benefited thus far from the improved health of Jacoby Ellsbury and Dustin Pedroia and the additions of Mike Napoli and Shane Victorino on offense, it's pitching that is truly driving the turnaround. Last year's collection ended up with the fourth-worst ERA in baseball; through the first month of 2013, they'd allowed the fifth-fewest runs in the game. Even more notable, however, is how they're getting there, because this crew is striking out hitters at a record pace. After Jon Lester and Junichi Tazawa teamed to punch out seven Toronto Blue Jays to finish off April on Tuesday night, the Boston staff stood at a combined 9.94 strikeouts per nine innings.

That strikeout pace is more than two and a half batters more per game than the 2012 Red Sox had, which would be an enormous increase. Not only that, it would be the highest team rate in baseball history if they were somehow able to maintain it for the entire season. How have they managed to increase their strikeout rate so much?