The NFL is back up to six head coaching vacancies as new Jags GM Dave Caldwell fired Mike Mularkey after just one season at the helm. It doesn’t happen often, but it goes to show that one bad year can get you fired in the NFL. Greg Roman, the 49ers’ offensive coordinator, will be one of the leading candidates for the job. He and Caldwell were roommates and teammates at John Carroll University. The big takeaway from this is that the firing shows why Caldwell chose the Jags job over the Jets job. If he went to the Jets he would have been stuck with Rex Ryan for at least another year. That’s why the Jets are still struggling to find a general manager.