The 49ers, one of two remaining unbeaten teams in the NFL, are aggressively pursuing multiple options at wide receiver, league sources said, viewing an upgrade at the position as the key to a potential deep playoff run.

San Francisco has been much improved on both sides of the ball, with quarterback Jimmy Garoppolo finally healthy and one of the more balanced teams in the NFL thus far. However, head coach Kyle Shanahan, who runs the offense and has a keen eye for receiving talent as a former receiver coach, and the front office have identified receiver as an area of specific attention ahead of the trade deadline, which looms after Week 8.

The 49ers have been an aggressive team on the trade market in recent years, landing Garoppolo with an in-season blockbuster. They were pursuing Khalil Mack a year ago, were in the mix for Odell Beckham as well, and landed Dee Ford in an offseason deal. Despite all of their early-season success, the offense has room for growth in the passing game, with few proven options beyond All Pro tight end George Kittle, who has more than twice as many receptions as anyone else on the roster.

The 49ers are among a bevvy of teams with interest in Bengals star A.J. Green, but it remains to be seen if the winless team relents and deals the pending free agent. Emmanuel Sanders was drawing interest as well, but the Broncos are back in the mix in the AFC West after a woeful 0-4 start. A reunion with receiver Mohamed Sanu, who Shanahan coached in Atlanta and is not being featured in the Falcons offense, is quite possible, league sources said. Atlanta is falling out of contention despite a bloated roster, and a coaching change looms. Taylor Gabriel (Bears), who put up career numbers with Shanahan in Atlanta, is not seeing much of the ball in Chicago. Former Dolphins first-round pick Devante Parker, who has yet to show much or stay healthy since being selected in the first round, would likely be a fallback option, sources said.

Rookie receiver Deebo Samuel is second on the 49ers with just 15 catches through five games; no wide receiver on the roster has even 200 yards receiving thus far or more than one touchdown. Garoppolo is completing nearly 70 percent of his passes, and there is hope that youngster Dante Pettis can stay healthy and provide a boost, but the addition of one more legit pass-catching threat could be vital in the team being able to thrive against top defenses in December and January.