Left-handed hitters tagged the southpaw reliever for a .293 batting average and an .805 on-base-plus-slugging percentage, but right-handed hitters managed only a .193 batting average against the side-winder.

Lopez spent a portion of the offseason dissecting the phenomenon, and he harkened back to mound basics. The lefty utilized his changeup and slider to freeze right-handed hitters and improve his overall effectiveness, but his fastball command suffered as he lavished more attention on fine-tuning the junk.

"Obviously working ahead in the count is a good thing for me, but I think I got into a little bit of groove where I was throwing fastballs away," said Lopez, who has a 3.38 ERA in 12 games for the Sox this season. "Any left-handed hitter will tell (the outside fastball) is what they're looking for from anybody out of the bullpen -- especially a lefty specialist that is going to come in and throw that pitch because it's the toughest to hit.

"So I worked on really being able to move the fastball around along with working on my secondary stuff."

Red Sox pitching coach John Farrell called Lopez's changes a "counter-adjustment" to the approach left-handed hitters were taking against him, and ?- judging by the .188 batting average against to lefty batters this season -- the reliever seems to again have the drop on lefty swingers. Lopez ranks fourth among relievers in the American League in batting average against for left-handed hitters, and has paired with Hideki Okajima (.172 batting average against) to silence lefty hackers throughout the season.

"One of the main (improvements for Lopez) was getting inside on lefties and creating a little more depth to his slider," Farrell said. "He's throwing the sinker a little more to lefties, and he can change to two or three different arm angles. I think those counter-adjustments have been key against lefties."