Jacksonville Jaguars defensive tackle Marcus Stroud has been suspended for four games by the NFL for violating the league's steroids and related substances policy.

The suspension without pay applies with immediate effect and Stroud will not be eligible to return to the active roster until December 3.

A first-round draft pick in 2001, he is only one of two players in the history of the franchise to earn three consecutive Pro Bowl berths (2003-05).

The 6ft 6in, 306lb Stroud has 33 tackles, three sacks and nine quarterback pressures this season for Jacksonville (5-3).

The Florida Times-Union reported last week that Stroud's positive drug test resulted from "taking some supplements".

When his 'A' sample produced a positive result, Stroud exercised the right to have his 'B' sample tested according to the league's drug policy.

The Jaguars had previously signed free agent Grady Jackson to a one-year deal on October 30 in anticipation of Stroud's suspension.

Stroud had played in 68 consecutive games before missing five contests last season due to ankle and groin injuries and the seven-year veteran from Georgia underwent microfracture surgery during the off-season to repair a hole in the cartilage in his right ankle.

Jacksonville also placed guard Chris Naeole on injured reserve, ending his season. Naeole suffered a ruptured a quadriceps muscle during Sunday's 41-24 loss at New Orleans.