Since his hamstring injury, he doesn’t seem to be firming his front leg any more. When a hitter swings with a bent front leg, it means his body doesn’t have a base from which to rotate forcefully, which means slower hip rotation and less power.
Albert Pujols felt some tightness in his hamstring after running to first base in the seventh inning on April 24th. Since that time, he has been an even worse player than he was to begin the season.
Watch Pujols's hips in the first few seconds of the two videos Badler links to (home run on April 21, sac fly on May 6th). In the first video, his hips come right around and he knocks the ball out of the park. In the second video, it is as though he is moving in slow-motion.
Before leaving the April 24th game, Pujols had a rate of 23% home runs per fly ball. Since that day it is just 5%. His ground ball rate has been consistently around 50% all season. His career ground ball rate is 41%.
For the season, he is on pace to hit into 45 double plays, which would shatter the record of 36. Pujols has had about 250 plate appearances this year, so the sample size is large enough to start questioning things like ground ball rate and even almost home run rate.
The sample size between now and April 24th is still quite small, but when there is a legitimate reason for a poor performance, it at least needs to be talked about seriously.
This isn't the first time this has happened either. In 2006, Tony LaRussa mentioned this as Pujols had the same type of injury.
"He doesn't have that big power push," La Russa said. "He's not going to be generating as much power, but he can still generate base hits.
I'm with Ben on this one: Let's talk about this.