Friday marks the first date of importance of the MLB offseason, with this evening representing the deadline for teams to extend qualifying offers to impending free agents. Before we get into the Red Sox-specific portion of this, a primer. The previous CBA was the first to introduce the concept of a qualifying offer to MLB, and it replaced the old Type A/Type B free agent compensation system from last decade. Under the qualifying offer system, teams can offer any player who is set to hit free agency and who spent the entire season with the team a one-year deal worth the mean salary of the top 125 highest-paid players in the league.