Matt Damon had some advice for his fellow "Oppenheimer" star Josh Hartnett, but apparently it came a little too late.

Hartnett appeared on "The Tonight Show Starring Jimmy Fallon" earlier this week, laughing at Damon’s "unhelpful" suggestion.

"He gave me a lot of good advice," Hartnett said. "One in particular — one thing that was just so unhelpful: He told me not to gain the weight I’d already gained for the role."

He continued, "I gained about 30 pounds for the role, and he was like, ‘You’re never gonna get that off again, man. Don’t gain weight over 40. You’re going to spend the rest of your life trying to get that weight off and it’s never going to come off because your body is going to want to get that weight back on. You’re just going to keep growing back out to that size, and you’re going to try and get it off, and it’s just going to go back.’ He kept telling me over the course of production."

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In the film, the now 46-year-old Hartnett played Ernest Lawrence, a Nobel-winning physicist who worked with J. Robert Oppenheimer. Damon, 53, played Lt. General Leslie Groves, director of the Manhattan Project.

"I was like, ‘Thanks, Matt. Thanks for telling me this now. I’ve already gained it,’" Hartnett joked. "And now I don’t eat anymore."

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Hartnett’s role is on the smaller side in "Oppenheimer," and he joked about the pressure being off during awards season while supporting the film.

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"It is kind of fun when you’re not up for any awards," he said. I just get to have a couple drinks with people and hang out and watch other people go up there and give speeches and make a fool of themselves and it’s great."

Fallon pointed out Oppenheimer won best picture at this year’s Oscars, and Hartnett said he got to go up on stage when that happened, adding, "If you look at all the pictures on the cover of The New York Times and all that, I was the one just off the edge of frame where they cut it. It was like, they included one of the ushers, not me."

The Canadian women’s soccer team was dealt a heavy blow Saturday after FIFA announced the women's national team would be deducted six points from the standings in the Paris Olympics after staffers were caught using drones to spy on New Zealand during closed-door training sessions.

Following its investigation, the FIFA Appeal Committee announced the Canadian Soccer Association was responsible for failing to ensure its staff members were in compliance with Olympic rules. 

"CSA was found responsible for failing to respect the applicable FIFA regulations in connection with its failure to ensure the compliance of its participating officials of the Games of the XXXIII Olympiad Paris 2024 Final Competition (OFT) with the prohibition on flying drones over any training sites," the statement said. 

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"The officials were each found responsible for offensive behavior and violation of the principles of fair play in connection with the CSA’s Women’s representative team’s drones usage in the scope of the OFT." 

​​Head coach Bev Priestman was removed from her position Thursday night after two staff members were sent home from Paris when an investigation found that analyst Joseph Lombardi had allegedly used a drone to spy on New Zealand's practice sessions. 

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The revelation that there may have been previous unethical recordings of opponents comes amid Canada’s pursuit of a title defense in the Olympics. The women’s team won gold in Tokyo and won its first match against New Zealand Thursday before Priestman’s dismissal. 

FIFA said Saturday that Priestman, Lombardi and assistant coach Jasmine Mander were banned "from taking part in any football-related activity for a period of one year." Canada Soccer was also fined $226,000. 

Canada Soccer can appeal the decision before the Court of Arbitration for Sport. The points deduction, if upheld by the CAS judges, does not eliminate Canada from the tournament, but it could mean the team must win all three games in Group A to advance with three points, likely as a runner-up in the standings.

Canada's next match is Sunday against France. 

The Associated Press contributed to this report. 

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