Rob Ninkovich has started every game for the Patriots over the past five seasons. He'll likely miss significant time this year after tearing a triceps muscle Tuesday, according to ESPN.com.
Ninkovich left a joint practice with the Saints and will have an MRI exam later in the week to determine the severity of the injury.
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Ninkovich, a fifth-round pick of the Saints in 2006, has been with the Patriots since 2009. He became a starter in 2010 and has 42 career sacks, including 6 1/2 last season.