The Ravens said a month ago they wanted to strengthen the middle of their defense after winning the Super Bowl. They left out the part about letting more than half of their starting defenders go to accomplish that goal. On Wednesday, the Ravens released starting strong safety Bernard Pollard, a hard-hitting box safety who is a quality run defender. His release came a day after the Ravens lost inside linebacker Dannell Ellerbe and pass rusher Paul Kruger in free agency and a month after inside linebacker Ray Lewis ended his career with a title. In case you’re not adding it up at home, that’s a combined loss of 289 tackles, 16.5 sacks, two interceptions and four forced fumbles from 2012. Pollard and Ellerbe were the team’s leading tacklers during the regular season and Lewis led all players in tackles during the playoffs. Kruger led the team with nine sacks and Ellerbe added 4.5 sacks last season. The 16.5 sacks from those players were 44.6 percent of the team’s sack output. The losses will likely continue in the coming days. Starting free safety Ed Reed, cornerback Cary Williams and nose tackle Ma’ake Kemoeatu are all free agents and none are locks to return. That means the Ravens could potentially be without seven starters from the team that won the Super Bowl just a few weeks ago. Would that be unprecedented? Yes, the Ravens are on the way. According to the Elias Sports Bureau, no champion has lost more than five Super Bowl starters from their team before the following season. And that’s starters lost for the whole team -- not one unit. While the Ravens defense ranked 17th with 228.1 passing yards allowed per game and 20th with 122.8 rushing yards allowed per game, that unit got better as the season progressed and made critical stands during the postseason, including the final moments of the 34-31 win over the San Francisco 49ers in the Super Bowl. It’s clear, though, the Ravens will be getting younger on defense this spring, whether they wanted to be this young to or not.