Namely, she doesn't have to worry about sweating buckets while interviewing Robert De Niro and getting one-word answers.
Fallon remembered "being so sweaty" while interviewing the acting legend during his first week as a late-night host in 2009, but he ultimately made it through on his way to eventually becoming the host of "The Tonight Show."
He thought back to those days to dispense a simple piece of advice to Jenna on Tuesday during her second day as the co-host of the fourth hour of TODAY with Hoda Kotb.
"Take notes this whole week and then send yourself an email, like a happy email at the end of the week saying to yourself what I loved about this week,'' he told her. "... 'How lucky I am to do this.' Because there's gonna be tough days where you'll be like, 'I don't know, man.'
"And then you go, 'Happy email! Happy email!' And then read your happy email to remind you."
Jimmy still revisits his happy emails all these years later after a tough day.
"I have so many happy emails that I've kind of lost track of them,'' he said. "We're really lucky to have what we have here. It's worked. It's a good reminder."
As far as he's concerned, Jenna will be just fine as she succeeds Kathie Lee Gifford as co-host.
"You know how to do it, you're doing great,'' he said. "Just keep talking. You have a great crew, you have the best people/family surrounding you here."
Hoda and Jenna also had Jimmy sweating when they made him the inaugural guest to play their new game called "On the Spot" under the glare of the spotlight.
"I feel like a chicken nugget right now," he joked.
They peppered him with rapid-fire questions to find out that he likes dogs over cats, the Yankees over the Mets and the compromise of boxer briefs instead of boxers or briefs.
They really put him on the spot when they asked him to identify his least favorite song from his good friend Justin Timberlake.
"'Feathers,''' he said. "I just made that up."
He also revealed that his dressing room contains a rubber band ball, an air freshener shaped like "The Walking Dead" star Norman Reedus, and a plaque given to him by actress Kerry Washington that reads, "Not today, Satan!"
Finally, they asked him a question that was too hot for the spot: What is your least favorite game on your show?
"I'm jumping off the spot!" he said.