As first reported by Ken Rosenthal, it appears the Red Sox have made another minor move in search of starting pitching depth, signing longtime Rockie Aaron Cook to a minor league contract. Cook will probably not be a game changer, but he has been in the league since 2002, and he is worth taking a more detailed look at.
Cook is going to be entering his age-33 season in 2012, so he isn't completely over the hill age-wise. He had two successful seasons in Colorado, producing 4.3 and 4.7 fWAR in 2006 and 2008, respectively. He did this mainly by preventing walks and forcing ground balls. He has a career 2.80 BB/9 ratio, and held that number under three for five consecutive years from 2005 through 2009. However, one of the reasons he never saw any major success in Denver was that he totally lacks the ability to strike people out. He actually set a career high in K/9 in 2011, but it was just a measly 4.45. Because of his lack of strikeouts, he has had one season with a FIP below four, and every other season stays in the 4-range. Basically, you know what you are getting from Aaron Cook. Low strike-outs, low walks, average-to-good home run prevention and high ground ball percentage.
The reason for Cook's ground ball numbers are mainly due to his sinker, which he has thrown around 60% of the time the past two years. His fastball is far from overpowering, and he has been moving away from it the last two years. As his career has gone on, his velocity has steadily dropped to the 88-mph fastball he now throws. He also throws two breaking balls, a slider and a curveball, but both of those lead to more ground balls than missed bats.
In the end, Cook was probably a good low-risk move for the Red Sox to make. Since he just signed a minor league deal, if he stinks the team can easily rid themselves of him. However, if he proves to be a competent pitcher, the team can keep in Pawtucket and call him up in case of emergency situations when starters go down with injuries. He reminds me of the Kevin Millwood signing last year, who ended up in Colorado by the end of the year, strangely enough. So while Cook is not the sexiest signing in the world, his low walks and high ground ball rate could prove to work out for this team in emergency situations.