Amazing Race's Phil Keoghan Previews Finale Shocker: I Couldn't Believe It Happened

The Amazing Race kicked off Season 20 with what Phil Keoghan called the "most bizarre Pit Stop." On Sunday (8/7c, CBS), the season will close with the series' "biggest shocker ever." For the first time, the team who arrives first at the finish line will be turned around for not completing a task correctly. "We were shocked as the viewers are gonna be," Keoghan tells TVGuide.com. "We were like, 'What just happened?' ... I couldn't believe it happened. Never have we had to tell the team that comes in first that they didn't win the $1 million. But it's good to know we can still have firsts 20 seasons in!" Of course, that team still has a chance to win if they can rectify their mistake at the Roadblock before the next team arrives.
So which team — married couple Dave and Rachel, Big Brother's Brendon and Rachel, border patrol agents Art and JJ, or dating divorcees Vanessa and Ralph — makes the potentially fatal error? Keoghan, obviously, cannot reveal it, but the eyebrow-raising host has plenty to say about the two-hour finale (the fourth place team will be eliminated in Japan, with the final three racing in Hawaii), how he thinks the team screwed up and the cast's excessive bickering.

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I've been watching since the first season and have always wondered if a team will ever mess up on the last leg and get turned back when they think they've won. And now it finally happens.
Phil Keoghan: [Laughs] I guess you kind of hope sometimes things like that will happen — not that I'm wishing for anything bad to happen to people. But of course it makes it interesting every time something new happens. ... It's weird because we've had it happen so many times on other legs, where a team has come in and not completed the course properly, and it's just never happened at the finish line ... It was a real surprise to all of us. It's not something we've sat around and talked about like, "Oh, can you imagine if we're on the final leg and a team comes in and doesn't complete the course?" We were all just like, "Did that just happen?" Normally when a team runs in to the mat, it's done and dusted. If they see somebody on the mat, they know they're not first. If they see a clear mat, they think, "We just won The Amazing Race!" And certainly, this team came to the mat thinking they had just won The Amazing Race. Everything for them, running in — even the teams standing there didn't know — everybody's cheering, they've already cashed the check [in their minds], they jump and they're like, "What? We have to do what?" You see the shocked reactions from the other teams. That's absolutely genuine. They didn't foresee it either.You hinted on Twitter that they didn't read the clue correctly. But I think a lot of people are wondering how they could get the next clue if they didn't complete the Roadblock. Or did they just stumble onto the next task without doing it?
Keoghan: We don't want to give it away because it's more complicated than [not reading the clue] — it's a lot of things. For this one team, they get told some news that they were not expecting to hear. Ultimately, everybody should read their clues. I think that and have your passport would be right up there. Know how to swim and drive stick. Those would be in the top five for sure.After the fact, could you understand how they messed up? Do you think it had to do with fatigue? There are a lot of physical challenges on the leg.
Keoghan: There are some mental challenges, but I think this is the big challenge with The Amazing Race. You're going back and forth all the time between physical and mental challenges. You have to switch parts of your brain, if you like. That is, I think, tough for teams. When it's physical, they're moving and they feel like they're getting ahead. They feel like they're making progress and sometimes it's just better to stop physical motion altogether and just think. Just because you're going somewhere doesn't mean you're actually getting ahead. This team gets to the mat first, but they didn't do everything correctly.Is there a memory challenge on the final leg?
Keoghan: Not a memory one, but there's a mental challenge. It's different this year. We're always trying to mix it up. But I think one of the best tasks is in the Japan leg with the Japanese game show they have to do [in which teams must grab dangling chickens while running on a conveyor belt]. (Check out a sneak peek below.)