FLOWERY BRANCH, Ga. -- Atlanta Falcons linebacker Sean Weatherspoon was placed on injured reserve with a designation to return with a foot injury.
Weatherspoon will miss the next eight weeks and is eligible to be activated for the Nov. 17 game against the Tampa Bay Buccaneers.
With Weatherspoon out, the Falcons will start undrafted rookie Joplo Bartu, who played 63 snaps Sunday against the St. Louis Rams. Veterans Jamar Chaney and Omar Gaither were signed to improve depth.
"In the preseason, we used (Bartu) exclusively one game and we wanted to see how he handled it," coach Mike Smith said. "He earned the opportunity to go out there and play in our (nickel) package. I thought he did a good job. He made a great tackle there early on the first drive when they were backed up. It was a text book open-field tackle. I think he will continue to get more reps."
Chaney was a seventh-round pick by Philadelphia in 2010 and has played in 44 games over three NFL seasons. Gaither was a fifth-round pick by the Eagles in 2006, who signed with Carolina in 2011 and spent last season with Oakland.
Weatherspoon is the third Falcons starter to be placed on injured reserve this week, following fullback Bradie Ewing and defensive end Kroy Biermann, who are on season-ending injured reserve.
To replace Ewing, the Falcons signed fullback Patrick DiMarco to the active roster and added linebacker Chase Thomas to the practice squad.
DiMarco was signed by New Orleans as an undrafted rookie out of Stanford last spring and spent time in training camp with the Saints and Raiders.