Agent: Brandin Cooks out 4-6 weeks

— -- METAIRIE, La. -- More bad news stemming from the New Orleans Saints' ugliest loss of the season: Rookie receiver Brandin Cooks suffered a broken thumb that could sideline him for an estimated four to six weeks, his agent said.

Cooks had surgery Monday.

He told fans on Twitter that there's nothing to worry about in terms of his recovery.

Cooks is having a standout season, leading all NFL rookies with 53 receptions for 550 yards and three touchdowns. He recently had begun to emerge as the Saints' most dynamic playmaker outside of tight end Jimmy Graham, mixing more deep balls into his repertoire.

The speedy first-round draft pick from Oregon State has done most of his damage on shorter plays such as screen passes and end-around runs designed to get him in open space.

Traditionally, the Saints' offense has been deep enough to absorb the loss of any one playmaker. Cooks' injury, however, comes at a time when the offense has been sagging.

The Saints (4-6) just lost 27-10 to the Cincinnati Bengals -- their lowest scoring output at home since 2006. New Orleans didn't have a play of longer than 17 yards.

The Saints, who still rank second in the NFL in total offense and third in passing offense, have six experienced receivers on the roster but veteran Robert Meachem has also been dealing with an ankle injury. Backups  Joseph Morgan and Nick Toon and pass-catching running back Travaris Cadet could become more important in the short term.

The Saints will mostly rely heavily on Graham and starting receivers Marques Colston and Kenny Stills. It would also help if they could get running back Pierre Thomas back from shoulder and rib injuries, as he's also a big part of the screen passing game.

Cooks will also need to be replaced as the Saints' punt returner, as Cadet is listed as the backup on the depth chart. The Saints rank 31st in the NFL with just 3.5 yards per punt return.

In other Saints injury news, a league source confirmed The New Orleans Advocate's report that safety Rafael Bush suffered a broken fibula instead of a broken tibia on Sunday, as Bush first indicated. It's possible that could mean a quicker recovery time, but it remains unclear if Bush will be placed on injured reserve.

Saints coach Sean Payton declined Monday to comment or speculate on any injuries.