The then redshirt freshmen raised his right hand to his head as a nod to the service men and women on hand for Clemson's 34-21 win over Virginia in 2009.
Allen was flagged for excessive celebration, and head coach Dabo Swinney was none too happy.
"I got chewed out pretty bad for that salute, by coach Swinney -- the rest of the first half, during halftime, coming out at halftime," said Allen, now a redshirt junior. "There won't be any celebrations from me [this year]."
New conduct rules have helped drive home that lesson.
According to the NCAA:
"Under the new rule, if a player makes a taunting gesture to an opponent on the way to scoring a touchdown, for example, the flag would nullify the score and penalize the offending team 15 yards from the spot of the foul. So if the gesture occurs at the 10-yard line, the offense would retain possession of the ball with the snap occurring at the 25-yard line.
"Penalties for dead-ball misconduct fouls (for example, unsportsmanlike behavior after the player crosses the goal line) would continue to be assessed on the ensuing kickoff or the extra point/two-point conversion attempt."
Clemson coaches stressed the new rule during preseason camp.
They went so far as to script Tajh Boyd high-stepping into the end zone on a touchdown run during one of the stadium scrimmages.
"They have really harped on it -- just act like you've been there before, and the importance of that new rule, and the touchdown can be taken off the board," Allen said. "That's great. Rules are there for a reason. I understand that."
But, as an offensive player, he would like to see the rule applied to players on the other side of the ball.
"I just wish it went both ways. I feel like a touchdown to a defensive player would be a sack. They get up and celebrate all they want after a defensive play and there's no penalties for excessive celebration.
"I just wish it went both ways."
Also new to the rulebook this season is a 10-second rundown in the final minute of play.
Again, according to the NCAA:
"...that will be enforced this year is a 10-second rundown of the game clock if a team commits a foul that stops the clock in the final minute of both halves."
The opponent has three options in these instances:
1. Take the yardage penalty and the 10-second rundown.
2. Take the yardage penalty without the 10-second rundown.
3. Decline both the 10-second rundown and the penalty yardage.
While the new rules make sense on a certain level, it will take time to see if they have staying power over the long haul.
Even Swinney said during his Tuesday press conference he wouldn't be surprised if the excessive celebration rule was eliminated at some point.
"Depends how often it is called," he said. "Or it won't get called - and that's another issue. Lord knows I hope it's not at Clemson. All I worry about is us. Just score and then hand the ball to the ref."
Tigers take note of rule changes
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