The Denver Broncos will enter the 2015 NFL season as the reigning AFC West champions, a title they have held for the last four consecutive seasons.

Although they have been a dominating force in recent years, this upcoming season does bring some doubts. Future Hall of Fame quarterback Peyton Manning is now 39 years old, the rest of the division is improving as is the rest of the AFC, and the Broncos roster isn't as deep as it was last season. On top of losing defensive tackle Terrance Knighton, the Broncos will also be without Julius Thomas.

Thomas was an excellent target for the Manning after catching 24 touchdowns over the last two seasons. Julius Thomas was a critical piece in the Broncos offense because he opened so many things for Demaryius Thomas, especially in the red zone. Julius Thomas had the most receiving touchdowns on the Broncos last season. But, Julius Thomas is gone, having signed a contract with the Jacksonville Jaguars this offseason, and it wouldn't hurt for John Elway to find an extra target to help Manning.

One option for the Broncos is to re-sign Wes Welker.

Welker has met with multiple teams this offseason, including the Miami Dolphins, but he remains a free agent. Welker is past his prime, and he does have some head issues because of the way he plays in the slot, but there are a few upsides to signing him. He knows the system having played with the Broncos over the last two seasons. In 2013, Welker had a career-high 10 receiving touchdowns with the Broncos.

He wouldn't provide the same big body as Thomas, but he could fulfill the same short yardage production in the slot and the red zone. Quick two second passes at the line of scrimmage to Welker could still be a good connection to move the chains for the Broncos. Welker's stock is lower than ever, so he won't cost the Broncos much at all. A possible contract between the sides most likely wouldn't cost more than $4 million guaranteed.

Another option for the Broncos is Reggie Wayne. Wouldn't this be something to see, as Manning and Wayne made up one of the greatest quarterback-wide receiver duos in NFL history on the Indianapolis Colts. While it's unlikely they can mimic that incredible performance once again, Wayne and Manning can still get the job done.

Wayne may be 36 years old, but he still had 779 receiving yards last season. A Wayne, Demaryius Thomas and Emmanuel Sanders trio could be something special to watch. Sanders is a great deep ball threat, Thomas can run virtually any route similar to Dez Bryant, and Wayne still has great hands to make plays in average yard gains.

Wayne won't be stretching the field past defenders 50 yards like he did with the Colts, but he still has great hands and he can get open for first downs. Welker does have head injuries, but he still did play in 14 games last season. Neither of these two players are in their prime, but adding one of them to the roster could be very beneficial.

Other notable free agent wide receivers include Greg Jennings, Hakeem Nicks and Brandon Lloyd.

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