The Detroit Lions wasted little time adding to their draft haul. After making seven selections in this year's Draft, general manager Brad Holmes and the Lions' front office quickly hit the phones to bring in undrafted free agents. There are some intriguing additions who could be factors in competitions for roster spots in training camp. Holmes and company have been generally open to keeping undrafted free agents. Their roster is a meritocracy, meaning they allow players to compete for jobs and allow for players who enter as undrafted free agents to truly battle for spots. Here is a ranking of the nine reported undrafted free agent signings made by the Lions in the days following the Draft. 9.) OL Melvin Priestly Priestly started every game this past season at right tackle for Illinois, but some evaluators believe he will be better suited at guard at the professional level.…