Graham couldn't resist following up a touchdown catch from quarterback Luke McCown with one of his trademark dunks over the goal post - a celebration that will be illegal beginning this season.
And since a crew of NFL officials was on hand to call the scrimmage, Graham promptly drew a flag - which promptly drew a chorus of boos from the fans in attendance.
It was all in good fun. But unfortunately for Graham, the NFL is indeed serious about banning the TD celebrations.
In part because Graham himself has knocked some goal posts ajar in past years, the NFL decided to add slam dunks to the longstanding taunting rule which prohibits using the ball as a prop.
NFL referee Gene Steratore and his crew were in town for the last few days to break down some of the new rule changes and points of emphasis with the Saints and officiate some of their practices (something the officials do with every team). And he told a group of Saints media members earlier Saturday morning that the question had come up whether things like finger rolls or dunks where the goal post isn't touched would be allowed.
"That was the question I had yesterday," Steratore said, according to The Advocate. "But no, (that's a) prop. We just have to go prop. ...
"I'd have to cheer you for (being able to dunk without touching the crossbar). But we can't. We have to start drawing the line."
Graham wasn't available for comment after Saturday's scrimmage. But he said last month that he would have to figure out an alternative TD celebration.
"I am going to listen to the rules and I understand the consequences," Graham told the Saints' web site. "I don't want to hurt the team, but I really just don't know what to do now (laughter)."
There were two bright spots for Graham, though.
One, he looks primed to have plenty of opportunities to find a TD celebration he likes. Graham looked great in Saturday's scrimmage, even though Drew Brees sat out because of an oblique strain. Graham caught a deep ball from quarterback Ryan Griffin before catching the short TD pass from McCown.
And secondly, Steratore said he joked with Graham that it might one day mean something special to him that he inspired a rule that could go down in history as, "the Jimmy Graham rule."