In early July Justin Morneau had been plodding through a season in which he was completely lost at the plate against left-handed pitching.

Even though his performance against right-handed pitchers was classic Morneausie, against the sinister his swing was basically a clusterbleep. His front side leaking so far open, he was left with little choice but to pull the ball. Left-handed opponents attacked this weakness by throwing more sliders which would run away from his swing zone. He flailed away helplessly as southpaws painted the outer-half of the plate and anything he did manage to put lumber on was typically bounced to the right side of the infield.

By the end of June his average against lefties had sunk to below .100 and was the worst in baseball. In a little over a month however Morneau has doubled that average - .174 heading in to last night's game – and, what's more, his swing has looked 100 times better.

Last night, the Twins' Director of Baseball Communications, Dustin Morse, highlighted Morneau's improvement against same-sided pitchers by tweeting this:

Now, the answer could be as simple as a small sample size fluctuation and that his suppressed batting average on balls in play was due to shoot up once the Baseball Gods felt like blessing the Canadian. However, just a few weeks before this streak started, Morneau made a noticeable adjustment to his approach at the plate. While this tweak lasted just a handful of games, the Twins first baseman emerged a different hitter.

Morneau, who had a sizeable stride accompanied by a hearty swing, was hitting just .229/.301/.435 heading into the final June series against the Kansas City Royals when he made the changes. Instead of the leg lift, Morneau would lift only his heel, keeping his toes stationary which would likely increase his connectivity and, more importantly, help him refrain from opening up his front side.

As I described back in the beginning of July:

This mechanical adjustment did not last long – somewhere around five games – and Morneau returned to his previous swing on July 5. But this practice seems to have righted the ship and helped him stay on the ball better. In addition to the improved numbers against left-handed pitching, he hit .313/.360/.488 overall in 86 plate appearances (not including last night's game against Boston). He had gone from striking out in 20% of his plate appearances pre-July 5 to striking out in just 10% of his plate appearances since then.

Of course, he has hit only three big flies in the past 20 games leaving questions about his power but, in short, Morneau appears to be on the right path both against righties and lefties. Friday night, look for him continue this success against Boston's rookie lefty Felix Doubront – who has limited left-handed hitters to a .229 average.