The Lions workout Thursday was both longest and sharpest of camp, but the on-field efforts failed to steal top billing from a two high-profile visitors to the team's Allen Park, Mich., facility. NFL commissioner Roger Goodell and former coach and broadcaster John Madden watched a team they described as one of the league's most improved franchises. While the Lions' effort played second fiddle to their visitors' presence, it featured several important signs of progress.

Welcome back, Backus: OT Jeff Backus returned to practice for the first time since injuring his thumb in Saturday's workout. He wore protective equipment on both hands and was able to participate fully in drills. Backus was joined on the practice field Thursday by CB Jacob Lacey, who missed Tuesday's practice with a knee injury. Although Backus' return is encouraging, Detroit has key players facing injury issues. S Louis Delmas (undisclosed) and RB Mikel Leshoure didn't practice, and LB Stephen Tulloch watched the second half of practice with his knee wrapped by trainers. Tulloch is recovering from tendonitis that caused him to miss Lions offseason program.

D-Line dominance: The DL was nearly unstoppable in pass rush drills Thursday. The unit dominated Detroit's OL for an entire practice period, reaching a pylon designed to simulate a QB on all but a handful of plays. DEs Lawrence Jackson and Willie Young continue to play well while splitting reps in place of absent DE Cliff Avril. Their improvement has clearly lessened the impact of Avril's holdout on Detroit's training camp plans. By their own admission, the DL must provide more effective pressure in 2012 to ease the coverage burden on the secondary. The line's performance Thursday indicates they're well on their way to accomplishing that goal.

An “I” in team?: FB James Bryant's arrival in camp has signaled the return of the “I” formation as a central part of Detroit's team run drills. Without a true FB on the roster last season, the Lions' run offense consisted primarily of plays using single or split-back formations that limited the rushing game's effectiveness in short-yardage situations. For the second consecutive practice, Bryant opened large holes as the lead back in power drills, allowing deep back Kevin Smith to easily reach the second tier of the defense on several plays.

Back seven steps up: It's not often that pass coverage units get the better of the Lions' QBs, but Thursday's workout was the exception. CB Chris Houston and S John Wendling each made an interception, and most of the first- and second-team DBs made at least one impressive pass breakup during coverage drills. Not to be denied, LB Doug Hogue also made an interception. A string of solid workouts early in camp has solidified Hogue's place in Detroit's second-team LB lineup.

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