ESPN Buster Olney Blog

Aaron Cook is more of a country-and-western kind of guy, and as a result he didn't have a lot of input when the Rockies made their choices about what music should be played after a recent Colorado victory. And as he drove away from Coors Field on Sunday, he couldn't identify for sure what was being played. But whatever music it is, it's being played a whole lot, because the Rockies have reeled off 11 consecutive victories.

The winning streak began only a few days after Clint Hurdle was fired as the Colorado manager and replaced by Jim Tracy. It was a pivotal point for the Rockies, Cook believes, because the players understood that they were responsible for Hurdle's exit. "A lot of us realized that it wasn't him that wasn't out there executing," Cook said.

The Rockies' players, Cook thinks, have narrowed their focus and done a better job of concentrating on the challenge immediately before them -- on winning that day's game -- and that really started a couple of weeks ago in Houston. The Rockies lost the first three games of a four-game series against the Astros, and really had very little going for them. But Jason Hammel, who has been excellent for the Rockies this season, threw well, and Garrett Atkins broke out of an extended slump for a couple of homers.

Since then, the Rockies' pitching has been nothing short of superb, surrendering four runs or less during the entire winning streak. "I think we've been able to take the pressure off the hitters," Cook said. "A lot of games early in the year, we [in the rotation] were giving up two or three runs early, and the hitters were really not in a position to relax … Tulo [Troy Tulowitzki] was saying the other day, the clubhouse is a lot looser, and guys are expecting to win."

Cook's own turnaround came in late April. He has long been one of the best ground-ball pitchers in the majors, but early in the season he was allowing more fly balls than grounders -- a very bad thing for him, because the fly balls he allows are often turned into extra-base hits. Cook had an ERA of 10.22 after he got pounded by the Dodgers on April 18, and what was really frightening was that he had no idea why his sinker was flat or why his fastball didn't have the same movement. During the course of his career, he had become adept at self-diagnosis, at feeling flaws in his delivery, but in this case, he had no clue.

A session in front of a videotape machine with Rockies pitching coach Bob Apodaca illuminated the problem for him, however. Cook saw that just before he was driving forward in his delivery, he was leaning toward the plate, his body tilted forward slightly -- and because of this, his body was ahead of his arm in the synchronization of his mechanics. This was causing his front shoulder to turn open before his arm was in optimal position to throw, flattening out his sinker.

Cook made an adjustment in his bullpen session, staying upright rather than leaning, staying back long enough to create the necessary time for his arm to lock and load. Right away, he could see a difference; right away, there was a difference in performance. His ground ball ratio has increased by a factor of three since he made that adjustment, and his ERA is at 2.91 since.

The Rockies remain far behind the Dodgers in the NL West race, but they can't really think about L.A., Cook said. They have to continue to play with their narrow focus, an approach that has been working for them day after day for 11 straight days now, punctuated by music that Cook doesn't know but has grown to enjoy.

• Nothing can stop the Rockies these days, not even tornado sirens, writes Patrick Saunders.

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