"It was a freak deal," coach Mike Holmgren said Monday, adding Engram remained in the game.
More on Engram
How will Bobby Engram's injury affect Seattle? ESPN.com's Mike Sando checks in on the Seahawks, who have a bit of a roster crunch. Blog
• Fantasy spin: Engram's injury downgrades Hasselbeck
• Blogs: NFL Nation | Fantasy spins
Holmgren said the worst case for Engram would be missing three regular-season games and returning for facing the defending Super Bowl champion New York Giants on Oct. 5.
The 35-year-old Engram set a franchise record last season with 94 catches then skipped Seattle's offseason minicamps while in a dispute over a contract that expires after this season. The Seahawks are refusing to negotiate a deal beyond the one paying him $1.7 million this season.
The offense was also missing Pro Bowl quarterback Matt Hasselbeck on Monday, for the second consecutive day. He has a stiff back that first tightened while he played two series against the Vikings.
"He tweaked it a little bit in the game, did something," Holmgren said. "He's taking it easy, taking a couple of days."
When asked if Hasselbeck might miss Saturday's preseason game against Chicago, the coach said, "I suppose there's a chance, but we haven't even talked about it yet."
Holmgren said the injury is not a previous issue, just a one-time tweak from Friday's game.
"Now look it, if you ask Matt, he'll give you the history of his back since he was 11," Holmgren joked.
Hasselbeck didn't seem concerned after practice. He joked around while hosting a small group of grade-school boys in the locker room area.
NFL.com Video
2007 Highlight: Matt Hasselbeck pass to Bobby Engram for a 30-yard touchdown.
Also Monday, Seattle terminated the contract of former first-round draft choice Marcus Tubbs. The former starting defensive tackle kept having setbacks following surgery a year ago on his right knee.
The loss of Engram is more than a minor setback to Holmgren's offense, which is already ailing.
Nate Burleson is Seattle's only healthy, accomplished veteran wide receiver. Deion Branch, a former Super Bowl MVP, may not be ready for the opener and won't even test his surgically reconstructed left knee on the practice field until the first week of September.
Hasselbeck and Engram arrived together in Seattle in 2001.
"Bobby is a very important part of what we do offensively," Holmgren said. "The young-ins have to step up and play, we've said that already. And now they just have to do it for a while."
Those kids include second-year man Courtney Taylor, who is taking Engram's spot, plus third-year veteran Ben Obomanu, undrafted free agent Michael Bumpus from Washington State and former practice squad player Logan Payne.
Center Chris Spencer, who had shoulder surgery in the offseason, did not return as expected Monday from a back injury that has kept him out of training camp. Guard Steve Vallos, a seventh-round draft choice last year, is the first-team center trying to learn on the fly the line's pre-snap calls on blocking assignments.
"No way did he think he was going to be in this position six months ago -- and now here you are," Holmgren said of Vallos. "Who knows? He might be the starting center on opening day."
The early injuries to Engram and Branch may have a trickle-down effect on players who are trying to make the team elsewhere -- such as seventh-round pick Justin Forsett, a running back from California, or undrafted rookie safety Jamar Adams from Michigan.
Holmgren likes to keep a total of 11 wide receivers and running backs on his 53-man roster for the regular season. He may have to keep more receivers this season, if he holds to his plan of keeping Engram and Branch on the roster for the start of the season.
"Yeah, absolutely, we've talked about that very thing," Holmgren said. "Now even if I wanted to go a different way, you can't mess around because we will have two receivers who are going to be on the roster who will not be playing."
Engram still upset, may skip Seattle training camp
New extension for Flyers GM Holmgren
Flyers’ Timonen likely out of East final
