The Ravens have filled the final spot on their 53-man roster, signing defensive lineman Ufomba Kamalu off the New England Patriots’ practice squad, his agent announced Friday.Kamalu, 26, has three sacks and 12 tackles in 15 career games. He signed with the Houston Texans as an undrafted free agent in 2016.The third-year player spent time on the Arizona Cardinals’ practice squad last season before signing with the Patriots’ practice squad. He was promoted to New England’s active roster Dec. 21.The 6-foot-6, 295-pound Kamalu adds depth to the defensive front after outside linebacker Pernell McPhee’s likely season-ending triceps injury.Kamalu is the second former Patriot to be signed this week by the Ravens, who host New England in Week 9. On Thursday, the Ravens announced the signing of safety Jordan Richards.On Tuesday, the Patriots signed cornerback and special teams ace Justin Bethel, a day after he was released by the Ravens. The Ravens made the move to recoup a compensatory draft pick.