Marshall and 114kg rookie prop Andrew Fifita had to be separated by forward Chris Heighington during a tense face-off.
The problems came after Fifita put a shoulder shot on Marshall, who was clearly upset by the treatment from a player trying to make his mark at the club.
Fifita, who with identical twin brother David played in the Toyota Cup last year, confirmed that Marshall had taken offence at the tackle.
But Fifita stressed there was no malice intended in the tackle.
The 20-year-old said the hit was just a rookie prop trying to impress the coaching staff.
"Benji was going off and we just had a little push and shove and that . . . but that happens you know," Fifita said.
"I'm just a kid learning the game. I can't wait to get a run in the first trial and try to impress the right judges and go from there. It's unreal."
Wests Tigers captain Robbie Farah missed the flare-up, but he was sporting a cut in the corner of his right eye and a swollen left hand after the heavy training session.
There is no suggestion the Tigers hooker was involved in the incident, but he confirmed the Tigers had stepped up the intensity in the past month.
"I didn't see anything like that (the Marshall showdown), but I can tell you we've been ripping in, mouthguards and all," Farah said.
"It's a good thing to see at this time of the year. Now is the time of year when you do all the hard work to prepare for the season ahead."
Fifita made a name for himself monstering opponents in the Toyota Cup and was a key member of the Tigers side beaten 24-22 by Melbourne Storm in the grand final.
Last October, both Andrew Johns and Wendell Sailor labelled the front-rower, who originally hails from Griffith, as the best player in the decider.
The rookie prop is set to serve as a back-up for regular props Keith Galloway, Jason Cayless, Bryce Gibbs and Todd Payten.
Fellow Tigers rookie Robert Louis confirmed Heighington rushed in to stand up for Marshall and cool the situation.
"Yeah, Fifita got Benji with a pretty good shot and he wasn't too happy about it," Louis said.
"Then Heighno (Heighington) came running in to stand up for Benji."
The flare-up will be welcome news to Tigers fans as the 2005 premiers hope to play their first finals series since the watershed premiership - as long as Marshall doesn't get hurt fighting out of his weight division.