GREEN BAY, Wis. -- How much the Green Bay Packers value receivers Randall Cobb and Jordy Nelson won't be known until -- or if -- the team signs them to long-term contracts before they hit free agency next March.

But thanks to ESPN.com's Mike Sando, we have a better idea of how others in the NFL view the Packers' top-two receivers.

In an ESPN Insider piece, Sando looked at what he called a loaded 2015 free-agent receiver class and, with the help of two NFL general managers plus an offensive and defensive coach, ranked the class in order of the likelihood of cashing in on big contracts whether with their current teams or on the free-agent market.

Both Cobb and Nelson ranked high on the list.

The 29-year-old Nelson came in at No. 4 behind Dez Bryant of the Cowboys, Demaryius Thomas of the Broncos and Michael Crabtree of the 49ers. Cobb, 23, was fifth.

The rest of the list was Torrey Smith of the Ravens, Wes Welker of the Broncos, Cecil Shorts of the Jaguars, Roddy White of the Falcons and Hakeem Nicks of the Colts.

The Packers and Broncos were the only teams with two free-agent-to-be receivers on the list.

Nelson is in the final year of a three-year, $12.6 million extension that turned out to be a bargain for the Packers, while Cobb is in the final year of the rookie contract he signed as a second-round pick in 2011.

Here's what Sando wrote based on evaluations by those he consulted:

On Nelson: Nelson and Crabtree virtually tied for the third spot. Nelson has benefited from consistently outstanding quarterback play. Over the past three years, Nelson trails only Welker and Thomas among players on this list in yards receiving per game. He is second to Smith in yards per reception and second to Bryant in touchdowns.

Nelson has competition from his teammate, Cobb, on this list. Nelson is primarily an outside receiver, while Cobb plays from the slot. Nelson polled higher than Cobb on three of four ballots. The defensive coordinator had Nelson sixth, one spot below Cobb. "I would put Jordy after Crabtree, but before Cobb," one of the GMs said.

The other GM joined the offensive assistant in placing Nelson among his top three. "You have to value that outside guy," the second GM said. "But that inside slot receiver can do a lot of damage."

A third GM I spoke with put it this way: "Nelson fits a big role for them. I would have a hard time saying he would be a hugely paid guy, though. He'll generate interest, but not at the $10-$11 million level. I do think he will come in over Eric Decker, though."

On Cobb: At 23, Cobb is easily the youngest player on this list. He missed 10 games last season and one in each of his previous two. That leaves him tied with Crabtree for the most games missed over the past three seasons when isolating the 10 players on this list. Cobb caught four passes for 106 yards and two touchdowns after returning for the Packers' final two games, counting a wild-card playoff defeat to the 49ers.

"Cobb and Crabtree are interchangeable on my list," the offensive assistant said. "Cobb is the model person and will always show up on time. Crabtree comes off whinier, and the guy from Seattle (Richard Sherman) got in his head. Cobb is coming from the right program with Mike McCarthy, one with structure and discipline and doing the right things. Crabtree does play outside more, but I'd rather coach Cobb."