As rival front offices start to take seriously Dwyane Wade's frustration with his Miami Heat contract talks, several teams are pursuing the 12-time All-Star with offers in the $20 million-annual range, league sources told The Vertical.

Dwyane Wade averaged 23.7 points for the Heat last season. (Getty Images) More

The Chicago Bulls, Dallas Mavericks, Denver Nuggets and Milwaukee Bucks have started a courtship process that has included offers in length of two and three years and upward of $20 million a season – a salary the Heat so far have been reluctant to offer, league sources said.

The Nuggets and Bulls have been among the most aggressive pursuers of Wade, league sources said.

Milwaukee has been open to sitting down and talking with Wade, but it doesn't have the salary-cap space – nor yet the full inclination – to make that kind of a commitment to Wade, league sources said.

Wade grew up in Chicago and played college basketball at Marquette in Milwaukee.

The Heat's initial offer of $10 million annually – which would've constituted a 50 percent pay cut from his $20 million 2015-16 salary – deeply angered Wade, league sources told The Vertical. Even with the Heat planning to counter to a higher figure, league sources said, Wade has been insistent on starting to explore the market and meet with teams once he returns from an overseas vacation, league sources said.

Wade had an excellent season for the Heat, averaging 23.7 points and leading a depleted roster into a Game 7 of the Eastern Conference semifinals.

Wade has taken less than his maximum-salary value on three straight deals to allow the Heat to supplement the roster with top talent. This time, the Heat are trying to balance the re-signing of center Hassan Whiteside to a four-year, $98 million maximum deal with the pursuit of free agent Kevin Durant. There are some close to Wade wondering whether the organization is trying to drive him away, but the Heat insist they want Wade to finish his career with the franchise, sources said.

Wade has been part of three NBA championship teams in Miami.

Miami is awaiting its meeting with Durant on Sunday in the Hamptons outside New York, where president Pat Riley and owner Micky Arison will make a presentation to Durant.

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