The Pats designated Welker as their franchise player in February, so he will play under a one-year, $9.5 million contract during the upcoming season, The Boston Globe reported.
Under NFL rules, the two sides won't be able to negotiate again until after the season.
The 31-year-old Welker said in May he had hoped to reach a long-term deal before Monday's deadline, but no agreement materialized.
He hauled down 122 passes in 2011, giving him an NFL-best 554 receptions since 2007.
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