The NFL London series began in 2007, and interest in American football across the pond has only grown since.
Gridiron Magazine editor Matthew Sherry, who helped form the publication devote to covering the league in 2013 and has regularly covered each of the NFL's London games, has seen it first hand.
"(It's grown) significantly," Sherry said via email. "I do think, initially, there was an element of the whole thing being new and therefore attracting an immediate audience. But it's gone way beyond that now, with season-ticket sales hitting exceptionally high numbers and the fanbase proving its long-term sustainability. We've also seen a significant growth in magazine sales and subscriptions, as well as a broader range of commercial opportunities."
For the Rams and the Bengals, that bodes well for Sunday – though they're no stranger to large crowds in London.
Los Angeles, which is making its second appearance in London under head coach Sean McVay and third in four seasons overall, earned a 33-0 victory over Arizona before a crowd of 73,736 in 2017.
Cincinnati, which is playing in the series for the second time ever, played the Redskins to a 27-27 tie in 2016 in the first NFL international series game to go to overtime. The contest drew a sold-out crowd of 84,488, which at the time set an attendance record for an NFL game outside the U.S. The Eagles' 24-18 win over the Jaguars two years later broke the record with 85,870 fans on hand at Wembley Stadium.
Sherry began to notice the support rising as early as 2013.
"The games were clearly a significant part of the puzzle," Sherry said regarding the decision to form Gridiron. "I was a sports journalist for a national news agency and also a big NFL fan, and I covered the games for my job. Around the time of the magazine starting, you could really feel the momentum building towards the odd game in London turning to something more significant and sustainable."
This year, season tickets for all four NFL London games sold out.
Sherry compared the lively atmospheres of the games he's covered so far to a Super Bowl.
"It's the one oft-used, but it really is like a Super Bowl," Sherry said. "I say that having covered some Super Bowls where the crowd is very pro one team, like last year's was very New England. But, as a rule, Super Bowls differ in that you see all different jerseys and the in-stadium intensity doesn't quite reach the level of big home games. London ones are the same, although the recent Bears-Raiders one at Tottenham was a pleasant exception."
As Sherry mentioned, one unique element that both journalists and broadcasters notice throughout the stadium is all the different jerseys worn by supporters in attendance.
It obviously wouldn't be surprising to see Rams jerseys in the crowd on Sunday. Based on the jerseys he's seen throughout the crowds, Sherry said RB Todd Gurley is probably the most popular Rams player in London.
"It's either Todd Gurley or (defensive tackle) Aaron Donald," Sherry said. "I'd say probably just the former, but people are aware of how uniquely talented Donald is."
So far, those who have watched this year's NFL London games in person or from afar have been treated to competitive and entertaining contests. The Raiders defeated the Bears 24-21 on a go-ahead touchdown run by rookie RB Josh Jacobs with under two minutes left in the game, while the Panthers and the Buccaneers produced the third-highest combined point total in the history of the London games.
However, considering how well attended these games have been in the past, it's likely there still would've been a lot of excitement surrounding this matchup anyway.
"Truthfully, the interest is there regardless," Sherry said. "We've had some good games and bad games, but the fan interest is only growing and supporters just want to see NFL action."