Chicago Bears wide receiver Allen Robinson informed the team he would rather be traded if the two sides cannot reach an agreement on a new extension, sources close to the situation told ESPN's Dan Graziano.

The Chicago Tribune reported Tuesday that Robinson made a formal trade request in response to stalled contract talks.

Robinson, 27, is in the last season a three-year deal he signed with the Bears in the spring of 2018. The former Pro Bowl wideout will earn $13 million cash in 2020.

Robinson recently scrubbed references to the Bears from his social media accounts.

The Bears are aware of Robinson's unhappiness, sources told Graziano, but the receiver repeatedly took the high road whenever pressed by reporters on the issue.

"Again, for me it's never my focus," Robinson said of his contract last Tuesday, leading up to Chicago's comeback victory over the Detroit Lions.

"I've said that before. I'm not focused on that. I'm focused on the season. All that other stuff, I let it play out however it plays out. But that's not of my concern right now."

Robinson caught five passes for 74 yards on nine targets in Week 1.

Last season, Robinson led the Bears with 98 receptions for 1,147 yards and seven touchdowns -- despite playing on one of the league's worst offenses. Robinson spent four years in Jacksonville (2014 to 2017), where he earned an invitation to the Pro Bowl after catching 80 passes for 1,400 yards and 14 touchdowns in 2015.

Robinson suffered a season-ending knee injury in Week 1 of 2017, his final year in Jacksonville, and was not fully healthy for the Bears in 2018, yet still recorded 55 receptions for 754 yards and four touchdowns in 13 games played.

"When we work on these deals, we know how important A-Rob is to us not just as a player but as a teammate, Bears general manager Ryan Pace said on Sept. 7.

Furthering Robinson's frustration has been the rash of contract extensions awarded to wide receivers over the past month, including to Arizona's DeAndre Hopkins, the Los Angeles Chargers' Keenan Allen and the Los Angeles Rams' Cooper Kupp.

Hopkins' new deal is worth the most in terms of average salary ($27.250 million) among NFL receivers. Atlanta's Julio Jones ($22 million), Allen ($20.025 million) and Dallas' Amari Cooper ($20 million) all have agreements that will average at least $20 million over the life of their respective deals.

Robinson's expiring three-year contract with Chicago averages out to $14 million per season -- 15th in the league for wide receivers.