Now the former college tight end is trying to win a starting job along the offensive line for the Seahawks.
Gilliam has been working with the first-team offense this week at right tackle and is expected to start against the Kansas City Chiefs on Friday night.
''Especially in that environment and against those rushers it will be a good test for me. I'm excited for it,'' Gilliam said.
After a poor showing from the team's line last week, Gilliam has been inserted at right tackle as Justin Britt has been moved to left guard.
''Garry has had a really nice camp and then put it together Friday night. It showed up pretty good,'' offensive line coach Tom Cable said.
Gilliam's first big moment with the Seahawks came during the last postseason as Seattle faced a 16-0 deficit late in the third quarter against the Packers with a return Super Bowl trip sliding away.
Gilliam, who played three seasons at tight end at Penn State before moving to tackle as a senior, slipped behind the Packers on a fake field goal from the 19. Punter Jon Ryan wheeled out of his hold and lofted the ball to Gilliam for a touchdown that cracked the door open for Seattle's wild rally.
His athleticism as a former tight end is what intrigued the Seahawks coaching staff a year ago, when he signed with Seattle as an undrafted free agent. Gilliam mostly played as an extra offensive lineman in jumbo formations as a rookie.
''He's a really exciting prospect because he really looks exactly like the guys should look with their movement and all,'' head coach Pete Carroll said. ''We really do cherish the guys that get off the ball and move their feet well.''
The Seahawks' offensive line has been a work in progress all training camp. Gilliam had mainly been playing at left tackle behind starter Russell Okung. However, the team has used five different players at left guard with the first-team offense and the battle for the starting center job is unsettled as well.
Cable said he ''did not like the pass protection at all'' during Friday's opener against the Denver Broncos. Seattle quarterbacks were sacked seven times and the team gained just 181 yards offensively as the line struggled.
''We're trying to get the best guys out there in the huddle and then find out where they fit,'' Cable said.
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