When the Knicks traded for Derrick Rose in the offseason, they did so knowing his expiring $21.5 million contract would come off the books the following summer.

It seems now, though, according to ESPN.com’s Ian Begley, the ex-Bulls point guard is seeking a pay raise similar to the $153 million contract the Memphis Grizzlies gave Mike Conley over the summer, the most lucrative deal in NBA history.

Writes Begley:

And then there is the potential price tag. Some close to Rose have told friends he will seek a max contract this summer. For Rose, that pact would be for five years and nearly $150 million. The Knicks would need to use nearly all of their cap space to ink Rose to a max contract.

Rose did not show up for the Knicks’ Monday matchup against the New Orleans Pelicans, a game they trailed as many as 29 and lost, 110-96. He later said he missed the game to be with his mother, though he did not give the team notice beforehand. So this is weird timing.

He has also missed (or left early from) five games this season with back injuries.

The former league Most Valuable Player is averaging a modest 17.3 points and 4.5 assists per game. New York (17-21) is 11th in the Eastern Conference but is just three games behind the fifth-seeded Indiana Pacers.

We all want a pay raise, and Rose is no different. Professional basketball — though a high-paying, high-profile job — is a job, nonetheless. And as employees, we should all look to maximize our value and haul in as much income as humanly possible.

But unless he transforms into his spry 21-year-old self overnight, the Knicks guard is living in the past.

The salary cap is projected to climb this summer yet again, and more money will be doled out in free agency than ever before. But Rose — who hasn’t had nearly the impact on winning or the defense as, say, Conley has had in Memphis — is in limbo.

He’s played well enough for teams to know he can still play, but not well enough to garner a max contract. Rose virtually dies on screens, and his health is still in question.

As Begley pointed out, the Knicks would need to use all their cap space to sign him. As if they don’t have enough roster issues to address already.

So maybe a team takes a chance on Rose and nabs him for $150 million. Maybe no team bites, and he has to sign for less than he currently makes.

Either way, free agency will be interesting for Rose and the rest of the NBA. And if he gets his money, trust that he won’t be the only one.

There’s nothing wrong with Rose wanting that much money. Whether he gets it or not is another question.