Killer Instinct / Joseph Finder

Jason Steadman is a thirty-year-old sales exec for a major electronics company in Boston. He's witty and well-liked but, to the chagrin of his ambitious wife, it looks like Jason's career has hit a ceiling. He lacks the one thing that could help him get ahead: the KILLER INSTINCT
 
All that changes when Jason meets Kurt Semko, a former Special Forces officer just back from Iraq. Looking for a decent pitcher for the company softball team, Jason gets Kurt, who was once drafted by the majors, a job in Corporate Security. Soon, good things start to happen for Jason--and bad things start to happen to Jason's rivals. 
 
Too late does Jason discover that Kurt has been paving his path to the top by the most efficient, devious means available. Now that his new best friend has become the most dangerous enemy imaginable, Jason stands to lose far more than his job….