SALT LAKE CITY – Ish Smith wanted to re-sign with the 76ers, but knew it wasn't a guarantee. And he wasn't going to sit around and wait.

So the point guard has agreed to a three-year, $18 million deal with the Detroit Pistons, according to a source.  The Detroit News first reported that Smith reached an agreement.  A contract may not be signed until July 7.

"He wanted to come back to Philly, but they never called him," the source said.

The free-agency period started at 12 a.m. Friday. The Sixers had told Smith that they wanted him to come back as a reserve. However, Smith had not heard from the Sixers by 3:30 a.m., the source said, and that's when the North Carolina native accepted the Pistons offer.

"He said, 'Last year, I waited on Philly, and Philly did me in,' " the source said.

Last summer, Smith and everyone associated with him were under the impression that Sixers were going to re-sign him to a lucrative deal. That's because he had a very successful stint in Philadelphia after being claimed off waivers Feb. 21.

Confident that Smith would get a market-value offer from the Sixers,  his then agent turned down a $2.9 million deal from the Phoenix Suns. Then he turned down a $1.5 million offer from the Sacramento Kings.

One problem: The Sixers never negotiated a deal with him.

That's why Smith wasn't going to wait around again this summer, even though his heart was with the Sixers.

"That's the plan," the unrestricted free agent said Thursday of resigning with the Sixers, "but you never know. I'd like to come back to Philly. Philly has been home. The fans have been great. Everybody has been great.

"But you know how that negotiation stuff goes. It gets a little shaky. Last year, I thought I would get offered. I never got offered."

Follow and contact 76ers beat writer Keith Pompey on Twitter @PompeyOnSixers and on Instagram at PompeyOnSixers