Bradley sidelined after undergoing knee surgery
In addition to Brian Urlacher, who is boycotting voluntary off-season activities with the Bears because he's disenchanted with his $56.6 million contract that has four years remaining, defensive tackle Tommie Harris, defensive end Alex Brown and cornerback Charles Tillman were not at practice Wednesday.
Receiver Mark Bradley was at Halas Hall but not on the practice field as he recovers from arthroscopic surgery on his right knee earlier this month to clean up scar tissue.
Bradley, who wore a brace on his right leg, said he would be ready for the start of training camp, although the team said that was questionable.
Return specialist-wide receiver Devin Hester, tight end Desmond Clark, linebacker Jamar Williams and defensive end Dan Bazuin were in attendance Wednesday but did not practice.
Done deal: The move of veteran John Tait from left tackle to right tackle is under way. He took all his snaps with the first team at right tackle in Wednesday's practice.
Veteran John St. Clair lined up at left tackle, although that is expected to be a temporary situation with first-round pick Chris Williams taking over on the left side by the end of training camp, if not sooner.
Williams has been the left tackle on the second unit in off-season practices.
Tait has been the Bears' starter at left tackle the past three seasons. He also has played three seasons at right tackle, the first two with the Kansas City Chiefs.
Left guard remains unsettled, although it appears Terrence Metcalf will get the first opportunity to win the job since he worked with the starters Wednesday.
Back on track: Safety Mike Brown, who recently had his contract restructured to limit the Bears' financial responsibility if he suffers a debilitating injury for the fifth straight season, was running with the first team.
Brown suffered a season-ending torn ACL in last year's season opener. He has missed 43 of 64 games the past four seasons after playing in 64 straight -- starting 63 -- in his first four seasons.