After Denver's series-saving Game 5 win, Jackson pointed the finger at the Nuggets for their physical play and for attempting to take cheap shots at Golden State star Stephen Curry.
"They tried to send hit men at Steph," Jackson said in his postgame news conference after the Warriors' 107-100 loss Tuesday night at the Pepsi Center.
"There were some dirty plays early," Jackson said. "It's playoff basketball. It's all right. Make no mistake, we were up 3-1 [in the series] playing hard, clean physical basketball, not trying to hurt anybody."
Jackson's comments didn't sit well with Hastings, who played in the NBA from 1982-93.
"I thought he was classless," Hastings said on "The Dan Patrick Show" on Wednesday. "It didn't even need to be brought in there. There were two flagrant fouls called in that game, and neither one was against the Denver Nuggets."
Hastings and Jackson shook hands and appeared to have a pleasant conversation a little more than two hours before tipoff of Game 6 at Oracle Arena.
Jackson was fined $25,000 by the NBA on Thursday for making public comments in an attempt to influence the officiating.
Jackson reponded to Hastings' comments Thursday on "The Dan Patrick Show."
"To say it was classless, it was unfair of him," Jackson said.
Jackson took umbrage with one particular play involving Curry in Game 5.
"[The Nuggets took] a shot at his ankle, clearly," Jackson said. "That can't be debated."
Curry, who has a history of ankle injuries and is playing through a sprained left ankle suffered in Game 2 of the first-round series, later agreed with his coach.
As the series shifts back to Golden State for Game 6 on Thursday, Nuggets guard Ty Lawson, who has drawn the primary defensive assignment on Curry, isn't worried about another physical game.
"If they look at the tape, they did the same thing. The series just evened out," Lawson told The Denver Post on Wednesday. "I don't think they are going to retaliate."
"Whether they're taking cheap shots or not, we'll discuss that at the end of the series," Bogut said Tuesday night. "We need to match their physicality, and we're going to do that in Game 6."
Information from The Associated Press and ESPN.com's J.A. Adande was used in this report.