Roger Federer has won Wimbledon eight times, more than any other male singles player, but apparently even he can't get into the grounds without a membership card.

Federer joined The Daily Show with Trevor Noah and shared a hilarious story about a by-the-book security guard who wouldn't let him in without showing proof of membership:

The 20-time Grand Slam winner was travelling to London to get a second opinion on his injured knee, which forced him out of professional tennis near the end of his career. It was one of the first times Federer had been on the grounds of Wimbledon on a non-tournament month, and he admitted he wasn't sure where to go to get in.

“I am a member,” Federer jokingly confirmed to Noah on the show. “I didn't tell Wimbledon I was going to be there, and normally when I'm here, I'm playing and there are loads of people and I come in a different way. When you win, you're automatically a member, but I didn't have my membership card with me.”

That was a problem for the security guard, who didn't recognize Federer and was not having any of his explanation. No membership card, no entry, she said.

Out of options, Federer had to tell her he'd won the tournament eight times. “Believe me, I'm a member,” he laughed.

Not even that was enough for the strict guard, who still didn't seem to put two and two together and realize she was looking at one of the most prolific tennis players of all time:

“She deserves a raise; she was gangster,” Noah joked to Federer.

Eventually, it was a fan who spotted the 41-year-old and asked for a selfie, which got the attention of a few officials inside the grounds and earned him entry into the clubhouse.

“I thought about going over and giving a wave to the security guard afterwards,” Federer quipped. “But no, that's not me.”

Wimbledon's official Twitter account assured Federer that he was welcome anytime, but he'll probably never forget his membership card again.